Fused heterocyclic compounds, and compositions and uses thereof

ABSTRACT

Fused heterocyclic compounds are disclosed that have formula 1:  
                 
 
where A, B, L, N, R 1 , R 3 , R 4′ , Y and Z are as defined herein. The compounds and pharmaceutical compositions thereof are useful for the prevention and treatment of a variety of conditions in mammals including humans, including by way of non-limiting example, pain, inflammation, cognitive disorders, anxiety, depression, and others.

RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. §119 of U.S.Provisional Application No. 60/677,760, filed May 4, 2005, incorporatedherein by reference in its entirety for all purposes.

FIELD OF THE INVENTION

This invention relates to novel fused heterocyclic compounds of theclass tetrahydronaphthyridines and tetrahydropyrido[4,3-d]pyrimidinesand to pharmaceutical compositions containing such compounds. Thisinvention also relates to methods for preventing and/or treatingconditions in mammals, such as (but not limited to) arthritis,Parkinson's disease, Alzheimer's disease, asthma, myocardial infarction,the treatment and prophylaxis of pain syndromes (acute and chronic orneuropathic), neurodegenerative disorders, schizophrenia, cognitivedisorders, anxiety, depression, inflammatory bowel disease andautoimmune disorders, and promoting neuroprotection, using the fusedheterocyclic compounds and pharmaceutical compositions of the invention.

BACKGROUND OF THE INVENTION

Therapeutic strategies for the effective management of pain and centralnervous system disorders or diseases are sought.

International Patent Application, Publication Number WO 02/08221discloses diaryl piperazine and related compounds which are said to beuseful in the treatment of chronic and acute pain conditions, itch andurinary incontinence.

WO02/053558 describes certain quinazolone derivatives as alpha 1 A/Badrenergic receptor antagonists, and WO03/076427 and WO04/041259 bothdescribe compounds of the same class for use in the treatment of femalesexual dysfunction. WO04/56774 describe certain substitutedbiphenyl-4-carboxylic acid arylamide analogues having possibleapplication as receptor modulators. Also, WO03/104230 describes certainbicyclic pyrimidine derivatives, and US Published Application Serial No.20030092908 and WO02/087513 describe fused heterocyclic PDE7 inhibitors.

U.S. Pat. Nos. 3,424,760 and 3,424,761 both describe a series of3-ureidopyrrolidines that are said to exhibit analgesic, central nervoussystem, and pyschopharmacologic activities. These patents specificallydisclose the compounds 1-(1-phenyl-3-pyrrolindinyl)-3-phenyl urea and1-(1-phenyl-3-pyrrolidinyl)-3-(4-methoxyphenyl)urea respectively.International Patent Applications, Publication Numbers WO 01/62737 andWO 00/69849 disclose a series of pyrazole derivatives which are statedto be useful in the treatment of disorders and diseases associated withthe NPY receptor subtype Y5, such as obesity. WO 01/62737 specificallydiscloses the compound5-amino-N-isoquinolin-5-yl-1-[3-(trifluoromethyl)phenyl]-1H-pyrazole-3-carboxamide.WO 00/69849 specifically discloses the compounds5-methyl-N-quinolin-8-yl-1-[3-(trifluoromethyl)phenyl]-1H-pyrazole-3-carboxamide,5-methyl-N-quinolin-7-yl-1-[3-trifluoromethyl)phenyl]-1H-pyrazole-3-carboxamide,5-methyl-N-quinolin-3-yl-1-[3-(trifluoromethyl)phenyl]-1H-pyrazole-3-carboxamide,N-isoquinolin-5-yl-5-methyl-1-[3-(trifluoromethyl)phenyl]-1H-pyrazole-3-carboxamide,5-methyl-N-quinolin-5-yl-1-[3-(trifluoromethyl)phenyl]-1H-pyrazole-3-carboxamide,1-(3-chlorophenyl)-N-isoquinolin-5-yl-5-methyl-1H-pyrazole-3-carboxamide,N-isoquinolin-5-yl-1-(3-methoxyphenyl)-5-methyl-1H-pyrazole-3-carboxamide,1-(3-fuorophenyl)-N-isoquinolin-5-yl-5-methyl-1H-pyrazole-3-carboxamide,1-(2-chloro-5-trifluoromethylphenyl)-N-isoquinolin-5-yl-5-methyl-1N-pyrazole-3-carboxamide,5-methyl-N-(3-methylisoquinolin-5-yl)-1-[3-(trifluoromethyl)phenyl]-1N-pyrazole-3-carboxamide, 5-methyl-N-(1,2,3,4-tetrahydroisoquinolin-5-yl)-1-[3-(trifluoromethyl)phenyl]-1H-pyrazole-3-carboxamide.

German Patent Application Number 2502588 describes a series ofpiperazine derivatives. This application specifically discloses thecompoundN-[3-[2-(diethylamino)ethyl]-1,2-dihydro-4-methyl-2-oxo-7-quinolinyl]-4-phenyl-1-piperazinecarboxamide.

SUMMARY OF THE INVENTION

Fused heterocylic compounds, and pharmaceutical compositions thereof,having potency and selectivity in the prevention and treatment ofconditions that have been associated with neurological and inflammatorydisorders and dysfunctions are described herein.

In particular, compounds, pharmaceutical compositions and methodsprovided are used to treat, prevent or ameliorate a range of conditionsin mammals such as, but not limited to, pain of various genesis oretiology, for example acute, chronic, inflammatory and neuropathic pain,dental pain and headache (such as migraine, cluster headache and tensionheadache). In some embodiments, the compounds, pharmaceuticalcompositions and methods provided are useful for the treatment ofinflammatory pain and associated hyperalgesia and allodynia. In someembodiments, the compounds, pharmaceutical compositions and methodsprovided are useful for the treatment of neuropathic pain and associatedhyperalgesis and allodynia (e.g. trigeminal or herpetic neuralgia,diabetic neuropathy, causalgia, sympathetically maintained pain anddeafferentation syndromes such as brachial plexus avulsion). In someembodiments, the compounds, pharmaceutical compositions and methodsprovided are useful as anti-inflammatory agents for the treatment ofarthritis, and as agents to treat Parkinson's Disease, Alzheimer'sDisease, asthma, myocardial infarction, neurodegenerative disorders,inflammatory bowel disease and autoimmune disorders, renal disorders,obesity, eating disorders, cancer, schizophrenia, epilepsy, sleepingdisorders, cognitive disorders, depression, anxiety, blood pressure, andlipid disorders.

Accordingly, in one aspect, fused heterocyclic compounds are providedthat have formula 1:

wherein

-   -   A and B are independently selected from CR^(2′)R^(2′), CO, and        CS;    -   Y is CR^(2′)R^(2′);    -   W is selected from CR⁴ and N;    -   Z is selected from O and NR²;    -   L is a bond, substituted or unsubstituted alkylene, or        substituted or unsubstituted heteroalkylene;    -   R¹ and R³ independently are a substituted or unsubstituted        carbocyclic group or a substituted or unsubstituted heterocyclic        group;    -   R² is selected from hydrogen, alkyl, cycloalkyl, aryl and        aralkyl;    -   each R^(2′) is selected from hydrogen, substituted or        unsubstituted C₁-C₆ alkyl, substituted or unsubstituted C₃-C₈        cycloalkyl, substituted or unsubstituted aryl and substituted or        unsubstituted aralkyl;    -   R⁴ is selected from H, substituted or unsubstituted alkyl,        substituted or unsubstituted acyl, substituted or unsubstituted        acylamino, substituted or unsubstituted alkylamino, substituted        or unsubstituted alkythio, substituted or unsubstituted alkoxy,        substituted or unsubstituted alkoxycarbonyl, substituted or        unsubstituted alkylarylamino, substituted or unsubstituted        arylalkyloxy, amino, substituted or substituted aryl,        substituted or substituted arylalkyl, substituted or        unsubstituted sulfoxide, substituted or unsubstituted sulfone,        substituted or unsubstituted sulfanyl, substituted or        unsubstituted aminosulfonyl, substituted or unsubstituted        arylsulfonyl, sulfuric acid, sulfuric acid ester, substituted or        unsubstituted dihydroxyphosphoryl, substituted or unsubstituted        aminodihydroxyphosphoryl, azido, substituted or unsubstituted        carbamoyl, carboxyl, cyano, substituted or unsubstituted        cycloalkyl, substituted or unsubstituted cycloheteroalkyl,        substituted or unsubstituted dialkylamino, halo, substituted or        substituted heteroaryloxy, substituted or unsubstituted        heteroaryl, substituted or unsubstituted heteroalkyl, hydroxy,        nitro, and thio; and    -   R^(4′) is selected from R⁴ and -Z′-L′-R⁴, wherein Z′ is a bond,        NR^(2′), O, S, SO, SO₂, COO, or CONR^(2′) and L′ is C₁-C₆        alkylene;    -   or a pharmaceutically acceptable salt, solvate or prodrug,        stereoisomer, tautomer or isotopic variant thereof.

In one aspect, a fused heterocyclic compounds is provided having formula1a:

wherein

-   -   A is selected from CR^(2′)R^(2′), CO, and CS;    -   each of B and Y is CR^(2′); and    -   W, Z, L, R¹, R^(2′), R³, R⁴ and R^(4′) are as defined above with        regard to formula 1;

or a pharmaceutically acceptable salt, solvate, prodrug, stereoisomer,tautomer, or isotopic variant thereof.

In another aspect, pharmaceutical compositions are provided comprising afused heterocyclic compound of the invention, and a pharmaceuticalcarrier, excipient or diluent. The pharmaceutical composition cancomprise one or more of the fused heterocyclic compounds describedherein.

It will be understood that fused heterocyclic compounds of the presentinvention useful in the pharmaceutical compositions and treatmentmethods disclosed herein, can be pharmaceutically acceptable as preparedand used.

In another aspect, methods are provided for preventing, treating orameliorating a condition from among those listed herein, andparticularly, such condition as may be associated with, e.g., arthritis,asthma, myocardial infarction, lipid disorders, cognitive disorders,anxiety, schizophrenia, depression, memory dysfunctions such asAlzheimers disease, inflammatory bowel disease and autoimmune disorders,which method comprises administering to a mammal in need thereof anamount of one or more of the compounds as provided herein, orpharmaceutical composition thereof, effective to prevent, treat orameliorate the condition.

In yet another aspect, methods are provided for preventing, treating orameliorating a condition that gives rise to pain responses or thatrelates to imbalances in the maintenance of basal activity of sensorynerves in a mammal. The fused heterocyclic compounds provided hereinhave use as analgesics for the treatment of pain of various geneses oretiology, for example acute, inflammatory pain (such as pain associatedwith osteoarthritis and rheumatoid arthritis); various neuropathic painsyndromes (such as post-herpetic neuralgia, trigeminal neuralgia, reflexsympathetic dystrophy, diabetic neuropathy, Guillian Barre syndrome,fibromyalgia, phantom limb pain, post-masectomy pain, peripheralneuropathy, HIV neuropathy, and chemotherapy-induced and otheriatrogenic neuropathies); visceral pain, (such as that associated withgastroesophageal reflex disease, irritable bowel syndrome, inflammatorybowel disease, pancreatitis, and various gynecological and urologicaldisorders), dental pain and headache (such as migraine, cluster headacheand tension headache).

In one aspect, methods are provided for preventing, treating orameliorating a neurodegenerative disease or disorder in a mammal. Aneurodegenerative disease or disorder can, for example, be Parkinson'sdisease, Alzheimer's disease and multiple sclerosis; diseases anddisorders which are mediated by or result in neuroinflammation such as,for example, encephalitis; centrally-mediated neuropsychiatric diseasesand disorders such as, for example, depression mania, bipolar disease,anxiety, schizophrenia, eating disorders, sleep disorders and cognitiondisorders; epilepsy and seizure disorders; prostate, bladder and boweldysfunction such as, for example urinary incontinence, urinaryhesitancy, rectal hypersensitivity, fecal incontinence, benign prostatichypertrophy and inflammatory bowel disease; respiratory and airwaydisease and disorders such as, for example, allergic rhinitis, asthmaand reactive airway disease and chronic obstructive pulmonary disease;diseases and disorders which are mediated by or result in inflammationsuch as, for example rheumatoid arthritis and osteoarthritis, myocardialinfarction, various autoimmune diseases and disorders; itch/pruritussuch as, for example, psoriasis; obesity; lipid disorders; cancer; andrenal disorders Typically, the methods comprise administering aneffective condition-treating or condition-preventing amount of one ormore of the compounds as provided herein, or pharmaceutical compositionthereof, to the mammal in need thereof.

In additional aspects, methods are provided for synthesizing the fusedheterocyclic compounds described herein, with representative syntheticprotocols and pathways described below.

Other objects and advantages will become apparent to those skilled inthe art from a consideration of the ensuing detailed description.

BRIEF DESCRIPTION OF THE FIGURE

FIG. 1 provides a general synthetic scheme for preparing compoundsprovided herein.

DETAILED DESCRIPTION OF THE INVENTION DEFINITIONS

When describing the compounds, pharmaceutical compositions containingsuch compounds and methods of using such compounds and compositions, thefollowing terms have the following meanings unless otherwise indicated.

It should also be understood that, consistent with the scope of thepresent invention, any of the moieties defined herein and/or set forthbelow may be substituted with a variety of substituents, and that therespective definitions are intended to include such substituted moietieswithin their scope. By way of non-limiting example, such substituentsmay include, e.g., halo (such as fluoro, chloro, bromo), —CN, —CF₃, —OH,—OCF₃, C₂₋₆ alkenyl, C₃-C₆ alkynyl, C₁-C₆ alkoxy, aryl and di-C₁-C₆alkylamino.

“Acyl” refers to a radical —C(O)R, where R is hydrogen, alkyl,cycloalkyl, cycloheteroalkyl, aryl, arylalkyl, heteroalkyl, heteroaryl,or heteroarylalkyl, as are defined herein. Representative examplesinclude, but are not limited to, formyl, acetyl, cylcohexylcarbonyl,cyclohexylmethylcarbonyl, benzoyl, benzylcarbonyl and the like.

“Acylamino” refers to a radical —NR′C(O)R, where R′ is hydrogen, alkyl,cycloalkyl, cycloheteroalkyl, aryl, arylalkyl, heteroalkyl, heteroaryl,or heteroarylalkyl and R is hydrogen, alkyl, alkoxy, cycloalkyl,cycloheteroalkyl, aryl, arylalkyl, heteroalkyl, heteroaryl orheteroarylalkyl, as are defined herein. Representative examples include,but are not limited to, formylamino, acetylamino,cyclohexylcarbonylamino, cyclohexylmethyl-carbonylamino, benzoylamino,benzylcarbonylamino and the like.

“Acyloxy” refers to the group —OC(O)R where R is hydrogen, alkyl, arylor cycloalkyl.

“Alkoxy” refers to the group —OR where R is alkyl. Particular alkoxygroups include, by way of example, methoxy, ethoxy, n-propoxy,isopropoxy, n-butoxy, tert-butoxy, sec-butoxy, n-pentoxy, n-hexoxy,1,2-dimethylbutoxy, and the like.

“Substituted alkoxy” includes those groups recited in the definition of“substituted” herein, and particularly refers to an alkoxy group having1 or more substituents, for instance from 1 to 5 substituents, andparticularly from 1 to 3 substituents, selected from the groupconsisting of acyl, acylamino, acyloxy, alkoxy, substituted alkoxy,alkoxycarbonyl, alkoxycarbonylamino, amino, substituted amino,aminocarbonyl, aminocarbonylamino, aminocarbonyloxy, aryl, aryloxy,azido, carboxyl, cyano, cycloalkyl, substituted cycloalkyl, halogen,heteroaryl, hydroxyl, keto, nitro, thioalkoxy, substituted thioalkoxy,thioaryloxy, thioketo, thiol, alkyl-S(O)—, aryl-S(O)—, alkyl-S(O)₂- andaryl-S(O)₂-.

“Alkoxycarbonylamino” refers to the group —NRC(O)OR′ where R ishydrogen, alkyl, aryl or cycloalkyl, and R′ is alkyl or cycloalkyl.

“Aliphatic” refers to hydrocarbyl organic compounds or groupscharacterized by a straight, branched or cyclic arrangement of theconstituent carbon atoms and an absence of aromatic unsaturation.Aliphatics include, without limitation, alkyl, alkylene, alkenyl,alkenylene, alkynyl and alkynylene. Aliphatic groups typically have from1 or 2 to about 12 carbon atoms.

“Alkyl” refers to monovalent saturated aliphatic hydrocarbyl groupsparticularly having up to about 11 carbon atoms, more particularly as alower alkyl, from 1 to 8 carbon atoms and still more particularly, from1 to 6 carbon atoms. The hydrocarbon chain may be eitherstraight-chained or branched. This term is exemplified by groups such asmethyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, tert-butyl,n-hexyl, n-octyl, tert-octyl and the like. The term “lower alkyl” refersto alkyl groups having 1 to 6 carbon atoms. The term “alkyl” alsoincludes “cycloalkyl” as defined below.

“Substituted alkyl” includes those groups recited in the definition of“substituted” herein, and particularly refers to an alkyl group having 1or more substituents, for instance from 1 to 5 substituents, andparticularly from 1 to 3 substituents, selected from the groupconsisting of acyl, acylamino, acyloxy, alkoxy, substituted alkoxy,alkoxycarbonyl, alkoxycarbonylamino, amino, substituted amino,aminocarbonyl, aminocarbonylamino, aminocarbonyloxy, aryl, aryloxy,azido, carboxyl, cyano, cycloalkyl, substituted cycloalkyl, halogen,hydroxyl, heteroaryl, keto, nitro, thioalkoxy, substituted thioalkoxy,thioaryloxy, thioketo, thiol, alkyl-S(O)—, aryl-S(O)—, alkyl-S(O)₂—, andaryl-S(O)₂—.

“Alkylene” refers to divalent saturated aliphatic hydrocarbyl groupsparticularly having up to about 11 carbon atoms and more particularly 1to 6 carbon atoms which can be straight-chained or branched. This termis exemplified by groups such as methylene (—CH₂—), ethylene (—CH₂CH₂—),the propylene isomers (e.g., —CH₂CH₂CH₂— and —CH(CH₃)CH₂—) and the like.

“Substituted alkylene” includes those groups recited in the definitionof “substituted” herein, and particularly refers to an alkylene grouphaving 1 or more substituents, for instance from 1 to 5 substituents,and particularly from 1 to 3 substituents, selected from the groupconsisting of acyl, acylamino, acyloxy, alkoxy, substituted alkoxy,alkoxycarbonyl, alkoxycarbonylamino, amino, substituted amino,aminocarbonyl, aminocarbonylamino, aminocarbonyloxy, aryl, aryloxy,azido, carboxyl, cyano, halogen, hydroxyl, keto, nitro, thioalkoxy,substituted thioalkoxy, thioaryloxy, thioketo, thiol, alkyl-S(O)—,aryl-S(O)—, alkyl-S(O)₂— and aryl-S(O)₂—.

“Alkenyl” refers to monovalent olefinically unsaturated hydrocarbylgroups preferably having up to about 11 carbon atoms, particularly, from2 to 8 carbon atoms, and more particularly, from 2 to 6 carbon atoms,which can be straight-chained or branched and having at least 1 andparticularly from 1 to 2 sites of olefinic unsaturation. Particularalkenyl groups include ethenyl (—CH═CH₂), n-propenyl (—CH₂CH═CH₂),isopropenyl (—C(CH₃)═CH₂), vinyl and substituted vinyl, and the like.

“Substituted alkenyl” includes those groups recited in the definition of“substituted” herein, and particularly refers to an alkenyl group having1 or more substituents, for instance from 1 to 5 substituents, andparticularly from 1 to 3 substituents, selected from the groupconsisting of acyl, acylamino, acyloxy, alkoxy, substituted alkoxy,alkoxycarbonyl, alkoxycarbonylamino, amino, substituted amino,aminocarbonyl, aminocarbonylamino, aminocarbonyloxy, aryl, aryloxy,azido, carboxyl, cyano, cycloalkyl, substituted cycloalkyl, halogen,hydroxyl, keto, nitro, thioalkoxy, substituted thioalkoxy, thioaryloxy,thioketo, thiol, alkyl-S(O)—, aryl-S(O)—, alkyl-S(O)₂— and aryl-S(O)₂—.

“Alkenylene” refers to divalent olefinically unsaturated hydrocarbylgroups particularly having up to about 11 carbon atoms and moreparticularly 2 to 6 carbon atoms which can be straight-chained orbranched and having at least 1 and particularly from 1 to 2 sites ofolefinic unsaturation. This term is exemplified by groups such asethenylene (—CH═CH—), the propenylene isomers (e.g., —CH═CHCH₂— and—C(CH₃)═CH— and —CH═C(CH₃)—) and the like.

“Alkynyl” refers to acetylenically unsaturated hydrocarbyl groupsparticularly having up to about 11 carbon atoms and more particularly 2to 6 carbon atoms which can be straight-chained or branched and havingat least 1 and particularly from 1 to 2 sites of alkynyl unsaturation.Particular non-limiting examples of alkynyl groups include acetylenic,ethynyl (—C≡CH), propargyl (—CH₂C≡CH), and the like.

“Substituted alkynyl” includes those groups recited in the definition of“substituted” herein, and particularly refers to an alkynyl group havingI or more substituents, for instance from 1 to 5 substituents, andparticularly from 1 to 3 substituents, selected from the groupconsisting of acyl, acylamino, acyloxy, alkoxy, substituted alkoxy,alkoxycarbonyl, alkoxycarbonylamino, amino, substituted amino,aminocarbonyl, aminocarbonylamino, aminocarbonyloxy, aryl, aryloxy,azido, carboxyl, cyano, cycloalkyl, substituted cycloalkyl, halogen,hydroxyl, keto, nitro, thioalkoxy, substituted thioalkoxy, thioaryloxy,thioketo, thiol, alkyl-S(O)—, aryl-S(O)—, alkyl-S(O)₂— and aryl-S(O)₂—.

“Alkanoyl” as used herein, which can include “acyl”, refers to the groupR—C(O)—, where R is hydrogen or alkyl as defined above.

“Aryl” refers to a monovalent aromatic hydrocarbon group derived by theremoval of one hydrogen atom from a single carbon atom of a parentaromatic ring system. Typical aryl groups include, but are not limitedto, groups derived from aceanthrylene, acenaphthylene,acephenanthrylene, anthracene, azulene, benzene, chrysene, coronene,fluoranthene, fluorene, hexacene, hexaphene, hexalene, as-indacene,s-indacene, indane, indene, naphthalene, octacene, octaphene, octalene,ovalene, penta-2,4-diene, pentacene, pentalene, pentaphene, perylene,phenalene, phenanthrene, picene, pleiadene, pyrene, pyranthrene,rubicene, triphenylene, trinaphthalene and the like. Particularly, anaryl group comprises from 6 to 14 carbon atoms.

“Substituted Aryl” includes those groups recited in the definition of“substituted” herein, and particularly refers to an aryl group that mayoptionally be substituted with 1 or more substituents, for instance from1 to 5 substituents, particularly 1 to 3 substituents, selected from thegroup consisting of acyl, acylamino, acyloxy, alkenyl, substitutedalkenyl, alkoxy, substituted alkoxy, alkoxycarbonyl, alkyl, substitutedalkyl, alkynyl, substituted alkynyl, amino, substituted amino,aminocarbonyl, aminocarbonylamino, aminocarbonyloxy, aryl, aryloxy,azido, carboxyl, cyano, cycloalkyl, substituted cycloalkyl, halogen,hydroxyl, nitro, thioalkoxy, substituted thioalkoxy, thioaryloxy, thiol,alkyl-S(O)—, aryl-S(O)—, alkyl-S(O)₂— and aryl-S(O)₂—.

“Fused Aryl” refers to an aryl having two of its ring carbon in commonwith a second aryl ring or with an aliphatic ring.

“Alkaryl” refers to an aryl group, as defined above, substituted withone or more alkyl groups, as defined above.

“Aralkyl” or “arylalkyl” refers to an alkyl group, as defined above,substituted with one or more aryl groups, as defined above.

“Aryloxy” refers to —O-aryl groups wherein “aryl” is as defined above.

“Alkylamino” refers to the group alkyl-N′—, wherein R′ is selected fromhydrogen and alkyl.

“Arylamino” refers to the group aryl-NR′—, wherein R′ is selected fromhydrogen, aryl and heteroaryl.

“Alkoxyamino” refers to a radical —N(H)OR where R represents an alkyl orcycloalkyl group as defined herein.

“Alkoxycarbonyl” refers to a radical —C(O)-alkoxy where alkoxy is asdefined herein.

“Alkylarylamino” refers to a radical —NRR′ where R represents an alkylor cycloalkyl group and R′ is an aryl as defined herein.

“Alkylsulfonyl” refers to a radical —S(O)₂R where R is an alkyl orcycloalkyl group as defined herein. Representative examples include, butare not limited to, methylsulfonyl, ethylsulfonyl, propylsulfonyl,butylsulfonyl and the like.

“Alkylsulfinyl” refers to a radical —S(O)R where R is an alkyl orcycloalkyl group as defined herein. Representative examples include, butare not limited to, methylsulfinyl, ethylsulfinyl, propylsulfinyl,butylsulfinyl and the like.

“Alkylthio” refers to a radical —SR where R is an alkyl or cycloalkylgroup as defined herein that may be optionally substituted as definedherein. Representative examples include, but are not limited to,methylthio, ethylthio, propylthio, butylthio, and the like.

“Amino” refers to the radical —NH₂.

“Substituted amino” includes those groups recited in the definition of“substituted” herein, and particularly refers to the group —N(R)₂ whereeach R is independently selected from the group consisting of hydrogen,alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl,substituted alkynyl, aryl, cycloalkyl, substituted cycloalkyl, and whereboth R groups are joined to form an alkylene group. When both R groupsare hydrogen, —N(R)₂ is an unsubstituted amino group.

“Aminocarbonyl” or “amido” refers to the group —C(O)NRR where each R isindependently hydrogen, alkyl, aryl and cycloalkyl, or where the Rgroups are joined to form an alkylene group.

“Aminocarbonylamino” refers to the group —NRC(O)NRR where each R isindependently hydrogen, alkyl, aryl or cycloalkyl, or where two R groupsare joined to form an alkylene group.

“Aminocarbonyloxy” refers to the group —OC(O)NRR where each R isindependently hydrogen, alkyl, aryl or cycloalky, or where the R groupsare joined to form an alkylene group.

“Arylalkyloxy” refers to an —O-arylalkyl radical where arylalkyl is asdefined herein.

“Arylamino” means a radical —NHR where R represents an aryl group asdefined herein.

“Aryloxycarbonyl” refers to a radical —C(O)—O-aryl where aryl is asdefined herein.

“Arylsulfonyl” refers to a radical —S(O)₂R where R is an aryl orheteroaryl group as defined herein.

“Azido” refers to the radical —N₃.

“Carbamoyl” refers to the radical —C(O)N(R)₂ where each R group isindependently hydrogen, alkyl, cycloalkyl or aryl, as defined herein,which may be optionally substituted as defined herein.

“Carbocyclic” refers to a cyclic carbyl group, which includes anaromatic group, a non-aromatic group or a non-aromatic group fused withan aromatic group. Examples of representative carbocyclics include thefollowing:

“Carboxyl” refers to the radical —C(O)OH.

“Carboxyamino” refers to the radical —N(H)C(O)OH.

“Cycloalkyl” refers to cyclic hydrocarbyl groups having from 3 to about10 carbon atoms and having a single cyclic ring or multiple condensedrings, including fused and bridged ring systems, which optionally can besubstituted with from 1 to 3 alkyl groups. Such cycloalkyl groupsinclude, by way of example, single ring structures such as cyclopropyl,cyclobutyl, cyclopentyl, cyclooctyl, 1-methylcyclopropyl,2-methylcyclopentyl, 2-methylcyclooctyl, and the like, and multiple ringstructures such as adamantanyl, and the like.

“Substituted cycloalkyl” includes those groups recited in the definitionof “substituted” herein, and particularly refers to a cycloalkyl grouphaving 1 or more substituents, for instance from 1 to 5 substituents,and particularly from 1 to 3 substituents, selected from the groupconsisting of acyl, acylamino, acyloxy, alkoxy, substituted alkoxy,alkoxycarbonyl, alkoxycarbonylamino, amino, substituted amino,aminocarbonyl, aminocarbonylamino, aminocarbonyloxy, aryl, aryloxy,azido, carboxyl, cyano, cycloalkyl, substituted cycloalkyl, halogen,hydroxyl, keto, nitro, thioalkoxy, substituted thioalkoxy, thioaryloxy,thioketo, thiol, alkyl-S(O)—, aryl-S(O)—, alkyl-S(O)₂— and aryl-S(O)₂—.

“Cycloalkoxy” refers to the group —OR where R is cycloalkyl. Suchcycloalkoxy groups include, by way of example, cyclopentoxy,cyclohexoxy, and the like.

“Cycloalkenyl” refers to cyclic hydrocarbyl groups having from 3 to 10carbon atoms and having a single cyclic ring or multiple condensedrings, including fused and bridged ring systems and having at least oneand particularly from 1 to 2 sites of olefinic unsaturation. Suchcycloalkenyl groups include, by way of example, single ring structuressuch as cyclohexenyl, cyclopentenyl, cyclopropenyl, and the like.

“Substituted cycloalkenyl” includes those groups recited in thedefinition of “substituted” herein, and particularly refers to acycloalkenyl group having 1 or more substituents, for instance from 1 to5 substituents, and particularly from 1 to 3 substituents, selected fromthe group consisting of acyl, acylamino, acyloxy, alkoxy, substitutedalkoxy, alkoxycarbonyl, alkoxycarbonylamino, amino, substituted amino,aminocarbonyl, aminocarbonylamino, aminocarbonyloxy, aryl, aryloxy,azido, carboxyl, cyano, cycloalkyl, substituted cycloalkyl, halogen,hydroxyl, keto, nitro, thioalkoxy, substituted thioalkoxy, thioaryloxy,thioketo, thiol, alkyl-S(O)—, aryl-S(O)—, alkyl-S(O)₂— and aryl-S(O)₂—.

“Fused Cycloalkenyl” refers to a cycloalkenyl having two of its ringcarbon atoms in common with a second aliphatic or aromatic ring andhaving its olefinic unsaturation located to impart aromaticity to thecycloalkenyl ring.

“Cyanato” refers to the radical —OCN.

“Cyano” refers to the radical —CN.

“Dialkylamino” means a radical —NRR′ where R and R′ independentlyrepresent an alkyl, substituted alkyl, aryl, substituted aryl,cycloalkyl, substituted cycloalkyl, cycloheteroalkyl, substitutedcycloheteroalkyl, heteroaryl, or substituted heteroaryl group, as aredefined herein.

“Ethenyl” refers to substituted or unsubstituted —(C═C)—.

“Ethylene” refers to substituted or unsubstituted —(C—C)—.

“Ethynyl” refers to —(C≡C)—.

“Halo” or “halogen” refers to fluoro, chloro, bromo and iodo. Preferredhalo groups are either fluoro or chloro.

“Hydroxy” refers to the radical —OH.

“Nitro” refers to the radical —NO₂.

“Substituted” refers to a group in which one or more hydrogen atoms areeach independently replaced with the same or different substituent(s).Typical substituents include, but are not limited to, —X, —R¹⁴, —O⁻, ═O,—OR¹⁴, —SR¹⁴, —S⁻, ═S, —NR¹⁴R¹⁵, ═NR¹⁴, —CX₃, —CF₃, —CN, —OCN, —SCN,—NO, —NO₂, ═N₂, —N₃, —S(O)₂O⁻, —S(O)₂OH, —S(O)₂R¹⁴, —OS(O₂)O⁻,—OS(O)₂R¹⁴, —P(O)(O⁻)₂, —P(O)(OR¹⁴)(O⁻), —OP(O)(OR¹⁴)(OR¹⁵), —C(O)R¹⁴,—C(S)R¹⁴, —C(O)OR¹⁴, —C(O)NR¹⁴R¹⁵, —C(O)O⁻, —C(S)OR¹⁴, —NR¹⁶C(O)NR¹⁴R¹⁵,—NR¹⁶C(S)NR¹⁴R¹⁵, —NR¹⁷C(NR¹⁶)NR¹⁴R¹⁵ and —C(NR¹⁶)NR¹⁴R¹⁵, where each Xis independently a halogen; each R¹⁴, R¹⁵, R¹⁶ and R¹⁷ are independentlyhydrogen, alkyl, aryl, arylalkyl, cycloalkyl, cycloheteroalkyl,heteroalkyl, heteroaryl, heteroarylalkyl, —NR¹⁸R¹⁹, —C(O)R¹⁸ or—S(O)₂R¹⁸ or optionally R¹⁸ and R¹⁹ together with the atom to which theyare both attached form a cycloheteroalkyl; and R¹⁸ and R¹⁹ areindependently hydrogen, alkyl, aryl, arylalkyl, cycloalkyl,cycloheteroalkyl, heteroalkyl, heteroaryl or heteroarylalkyl.

Examples of representative substituted aryls include the following

In these formulae one of R^(6′) and R^(7′) may be hydrogen and at leastone of R^(6′) and R^(7′) is each independently selected from alkyl,alkenyl, alkynyl, cycloheteroalkyl, alkanoyl, alkoxy, aryloxy,heteroaryloxy, alkylamino, arylamino, heteroarylamino, NR¹⁰COR¹¹,NR¹⁰SOR¹¹, NR¹⁰SO₂R¹⁴, COOalkyl, COOaryl, CONR¹⁰R¹¹, CONR¹⁰OR¹¹,NR¹⁰R¹¹, SO₂NR¹⁰R¹¹, S-alkyl, S-alkyl, SO-alkyl, SO₂-alkyl, S-aryl,SO-aryl, SO₂-aryl; or R^(6′) and R^(7′) may be joined to form a cyclicring (saturated or unsaturated) from 5 to 8 atoms, optionally containingone or more heteroatoms selected from the group N, O or S. R¹⁰, R¹¹, andR¹² are independently hydrogen, alkyl, alkenyl, alkynyl, perfluoroalkyl,cycloalkyl, cycloheteroalkyl, aryl, heteroaryl, heteroalkyl, or thelike.

“Hetero” when used to describe a compound or a group present on acompound means that one or more carbon atoms in the compound or grouphave been replaced by a nitrogen, oxygen, or sulfur heteroatom. Heteromay be applied to any of the hydrocarbyl groups described above such asalkyl, e.g., heteroalkyl, cycloalkyl, e.g. cycloheteroalkyl, aryl, e.g.heteroaryl, cycloalkenyl, cycloheteroalkenyl, and the like having from 1to 5, and especially from 1 to 3 heteroatoms.

“Heteroalkylene” refers to divalent saturated aliphatic hydrocarbylgroups particularly having up to about 11 carbon atoms and moreparticularly 1 to 6 carbon atoms which can be straight-chained orbranched and one or more carbon atoms in the group have been replaced bya nitrogen, oxygen, or sulfur heteroatom. This term is exemplified bygroups such as —(CH₂)₂SCH₂—, —(CH2)₃—SO₂CH₂—, —(CH₂)₂NHCH₂—,—(CH₂)₄OCH₂—, and the like.

“Substituted heteroalkylene” includes those groups recited in thedefinition of “substituted” herein, and particularly refers to aheteroalkylene group having 1 or more substituents, for instance from 1to 5 substituents, and particularly from 1 to 3 substituents, selectedfrom the group consisting of acyl, acylamino, acyloxy, alkoxy,substituted alkoxy, alkoxycarbonyl, alkoxycarbonylamino, amino,substituted amino, aminocarbonyl, aminocarbonylamino, aminocarbonyloxy,aryl, aryloxy, azido, carboxyl, cyano, halogen, hydroxyl, keto, nitro,thioalkoxy, substituted thioalkoxy, thioaryloxy, thioketo, thiol,alkyl-S(O)—, aryl-S(O)—, alkyl-S(O)₂— and aryl-S(O)₂—.

“Heteroaryl” refers to a monovalent heteroaromatic group derived by theremoval of one hydrogen atom from a single atom of a parentheteroaromatic ring system. Typical heteroaryl groups include, but arenot limited to, groups derived from acridine, arsindole, carbazole,β-carboline, chromane, chromene, cinnoline, furan, imidazole, indazole,indole, indoline, indolizine, isobenzofuran, isochromene, isoindole,isoindoline, isoquinoline, tetrahydroisoquinoline, isothiazole,isoxazole, naphthyridine, oxadiazole, oxazole, perimidine,phenanthridine, phenanthroline, phenazine, phthalazine, pteridine,purine, pyran, pyrazine, pyrazole, pyridazine, pyridine, pyrimidine,pyrrole, pyrrolizine, quinazoline, quinoline, tetrahydroquinoline,quinolizine, quinoxaline, tetrazole, thiadiazole, thiazole, thiophene,triazole, xanthene, and the like. Particularly, heteroaryl can includeother saturated ring systems, and can therefore be derived fromindoline, indolizine, tetrahydroquinoline, and tetrahydroisoquinoline.Preferably, the heteroaryl group is between 5-20 membered heteroaryl,with 5-10 membered heteroaryl being particularly preferred. Particularheteroaryl groups are those derived from thiophene, pyrrole,benzothiophene, benzofuran, indole, pyridine, pyrimidine, quinoline,tetrahydroquinoline, isoquinoline, tetrahydroisoquinoline, imidazole,oxazole and pyrazine.

Examples of representative heteroaryls include the following:

wherein each Y is selected from carbonyl, N, NR⁴, O, and S, where R⁴ isas defined herein.

As used herein, the term “cycloheteroalkyl” refers to a stableheterocyclic non-aromatic ring and fused rings containing one or moreheteroatoms independently selected from N, O and S. A fused heterocyclicring system may include carbocyclic rings and need only include oneheterocyclic ring. Examples of heterocyclic rings include, but are notlimited to, piperazinyl, homopiperazinyl, piperidinyl, morpholinyl, andinclude, for example, the following:

wherein each X is selected from C(R⁴)₂, NR⁴, O and S; each Y is selectedfrom NR⁴, O and S; where R⁴ is as defined herein and R⁷ is independentlyselected from the group consisting of acyl, acylamino, acyloxy, alkoxy,substituted alkoxy, alkoxycarbonyl, alkoxycarbonylamino, amino,substituted amino, aminocarbonyl, aminocarbonylamino, aminocarbonyloxy,aryl, aryloxy, azido, carboxyl, cyano, cycloalkyl, substitutedcycloalkyl, halogen, hydroxyl, keto, nitro, thioalkoxy, substitutedthioalkoxy, thioaryloxy, thioketo, thiol, alkyl-S(O)—, aryl-S(O)—,alkyl-S(O)₂— and aryl-S(O)₂—. Optionally, a cycloheteroalkyl can besubstituted, for example, with one or more groups selected from thegroup consisting of acyl, acylamino, acyloxy, alkoxy, alkoxycarbonyl,alkoxycarbonylamino, amino, aminocarbonyl, aminocarbonylamino,aminocarbonyloxy, aryl, aryloxy, azido, carboxyl, cyano, cycloalkyl,substituted cycloalkyl, halogen, hydroxyl, keto, nitro, thioalkoxy,substituted thioalkoxy, thioaryloxy, thioketo, thiol, alkyl-S(O)—,aryl-S(O)—, alkyl-S(O)₂— and aryl-S(O)₂—. Substituting groups includecarbonyl or thiocarbonyl which provide, for example, lactam and ureaderivatives.

Representative cycloheteroalkenyls include the following:

wherein each X is selected from C(R⁴)₂, NR⁴, O and S; and each Y isselected from carbonyl, N, NR⁴, O and S, where R⁴ is as defined herein.

Representative aryls having heteroatoms containing substitution includethe following:

wherein each X is selected from C—R⁴, C(R⁴)₂, NR⁴, O and S; and each Yis selected from carbonyl, NR⁴, O and S, where R⁴ is as defined herein.

“Hetero substituent” refers to a halo, O, S or N atom-containingfunctionality that may be present as an R⁴ in a CR⁴ group present assubstituents directly on W or Z of the compounds of this invention ormay be present as a substituent in the “substituted” aryl, heteroaryland aliphatic groups present in the compounds. Examples of heterosubstituents include: -halo, —NO₂, —NH₂, —NHR, —N(R)₂, —NRCOR, —NRSOR,—NRSO₂R, OH, CN, CO₂R, —CO₂H, —O—R, —CON(R)₂, —CONROR, —SO₃H, —S—R,—SO₂N(R)₂, —S(O)R, and —S(O)₂R, wherein each R is independently an arylor aliphatic, optionally with substitution. Among hetero substituentscontaining R groups, preference is given to those materials having aryland alkyl R groups as defined herein. Where feasible, each R may includehydrogen. Also, where feasible, two R groups when on same atom may jointo form a heterocyclic ring of 3-8 atoms. For example, two R groups ofNR², SO₂NR², and CONR² may join, together with the N atom, to form aN-morpholino, N-pyrrolo, N-piperidino, and N-pyrazolylo ring. Preferredhetero substituents are those listed above.

“Heterocyclic” refers to a cyclic group which includes a heteroaromaticgroup, a hetero non-aromatic or cycloheteroalkyl group, a non-aromaticgroup fused with a heteroaromatic group, a cycloheteroalkyl group fusedwith aromatic group and a cycloheteroalkyl group fused with aheteroaromatic group. Examples of representative heterocyclic groupsinclude the following:

wherein each X is selected from C—R⁴, C(R⁴)₂, NR⁴, O and S; each Y isselected from carbonyl, NR⁴, O and S; and where R⁴ and R⁷ are as definedherein.

“Dihydroxyphosphoryl” refers to the radical —PO(OH)₂.

“Substituted dihydroxyphosphoryl” includes those groups recited in thedefinition of “substituted” herein, and particularly refers to adihydroxyphosphoryl radical wherein one or both of the hydroxyl groupsare substituted.

“Aminohydroxyphosphoryl” refers to the radical —PO(OH)NH₂.

“Substituted aminohydroxyphosphoryl” includes those groups recited inthe definition of “substituted” herein, and particularly refers to anaminohydroxyphosphoryl wherein the amino group is substituted with oneor two substituents and/or wherein the hydroxyl group is substituted.

“Thioalkoxy” refers to the group —SR where R is alkyl.

“Substituted thioalkoxy” includes those groups recited in the definitionof “substituted” herein, and particularly refers to a thioalkoxy grouphaving 1 or more substituents, for instance from 1 to 5 substituents,and particularly from 1 to 3 substituents, selected from the groupconsisting of acyl, acylamino, acyloxy, alkoxy, substituted alkoxy,alkoxycarbonyl, alkoxycarbonylamino, amino, substituted amino,aminocarbonyl, aminocarbonylamino, aminocarbonyloxy, aryl, aryloxy,azido, carboxyl, cyano, cycloalkyl, substituted cycloalkyl, halogen,hydroxyl, keto, nitro, thioalkoxy, substituted thioalkoxy, thioaryloxy,thioketo, thiol, alkyl-S(O)—, aryl-S(O)—, alkyl-S(O)₂— and aryl-S(O)₂—.

“Sulfanyl” refers to the radical HS—. “Substituted sulfanyl” refers to aradical such as RS— wherein R is any substituent described herein.

“Sulfonyl” refers to the divalent radical —S(O₂)—. “Substitutedsulfonyl” refers to a radical such as S(O₂)—R wherein R is anysubstituent described herein. “Aminosulfonyl” or “Sulfonamide” refers tothe radical H₂N(O₂)S—, and “substituted aminosulfonyl” “substitutedsulfonamide” refers to a radical such as R₂N(O₂)S— wherein each R isindependently any substituent described herein.

“Sulfoxide” refers to the divalent radical —S(O)—. “Substitutedsulfoxide” refers to a radical such as S(O)—R, wherein R is anysubstituent described herein.

“Sulfone” refers to the group —SO₂R. In particular embodiments, R isselected from H, lower alkyl, alkyl, aryl and heteroaryl.

“Thioaryloxy” refers to the group —SR where R is aryl.

“Thioketo” refers to the group ═S.

“Thiol” refers to the group —SH.

One having ordinary skill in the art of organic synthesis will recognizethat the maximum number of heteroatoms in a stable, chemically feasibleheterocyclic ring, whether it is aromatic or non-aromatic, is determinedby the size of the ring, the degree of unsaturation and the valence ofthe heteroatoms. In general, a heterocyclic ring may have one to fourheteroatoms so long as the heteroaromatic ring is chemically feasibleand stable.

“Pharmaceutically acceptable” means approved by a regulatory agency ofthe Federal or a state government or listed in the U.S. Pharmacopoeia orother generally recognized pharmacopoeia for use in animals, and moreparticularly in humans.

“Pharmaceutically acceptable salt” refers to a salt of a compound of theinvention that is pharmaceutically acceptable and that possesses thedesired pharmacological activity of the parent compound. Such saltsinclude: (1) acid addition salts, formed with inorganic acids such ashydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid,phosphoric acid, and the like; or formed with organic acids such asacetic acid, propionic acid, hexanoic acid, cyclopentanepropionic acid,glycolic acid, pyruvic acid, lactic acid, malonic acid, succinic acid,malic acid, maleic acid, fumaric acid, tartaric acid, citric acid,benzoic acid, 3-(4-hydroxybenzoyl) benzoic acid, cinnamic acid, mandelicacid, methanesulfonic acid, ethanesulfonic acid, 1,2-ethane-disulfonicacid, 2-hydroxyethanesulfonic acid, benzenesulfonic acid,4-chlorobenzenesulfonic acid, 2-naphthalenesulfonic acid,4-toluenesulfonic acid, camphorsulfonic acid,4-methylbicyclo[2.2.2]-oct-2-ene-1-carboxylic acid, glucoheptonic acid,3-phenylpropionic acid, trimethylacetic acid, tertiary butylacetic acid,lauryl sulfuric acid, gluconic acid, glutamic acid, hydroxynaphthoicacid, salicylic acid, stearic acid, muconic acid, and the like; or (2)salts formed when an acidic proton present in the parent compound eitheris replaced by a metal ion, e.g., an alkali metal ion, an alkaline earthion, or an aluminum ion; or coordinates with an organic base such asethanolamine, diethanolamine, triethanolamine, N-methylglucamine and thelike. Salts further include, by way of example only, sodium, potassium,calcium, magnesium, ammonium, tetraalkylammonium, and the like; and whenthe compound contains a basic functionality, salts of non toxic organicor inorganic acids, such as hydrochloride, hydrobromide, tartrate,mesylate, acetate, maleate, oxalate and the like. The term“pharmaceutically acceptable cation” refers to a non toxic, acceptablecationic counter-ion of an acidic functional group. Such cations areexemplified by sodium, potassium, calcium, magnesium, ammonium,tetraalkylammonium cations, and the like.

“Pharmaceutically acceptable vehicle” refers to a diluent, adjuvant,excipient or carrier with which a compound of the invention isadministered.

“Preventing” or “prevention” refers to a reduction in risk of acquiringa disease or disorder (i.e., causing at least one of the clinicalsymptoms of the disease not to develop in a subject that may be exposedto or predisposed to the disease but does not yet experience or displaysymptoms of the disease).

“Prodrugs” refers to compounds, including derivatives of the compoundsof the invention,which have cleavable groups and become by solvolysis orunder physiological conditions the compounds of the invention which arepharmaceutically active in vivo. Such examples include, but are notlimited to, choline ester derivatives and the like, N-alkylmorpholineesters and the like.

“Solvate” refers to forms of the compound that are associated with asolvent, usually by a solvolysis reaction. Conventional solvents includewater, ethanol, acetic acid and the like. The compounds of the inventionmay be prepared e.g. in crystalline form and may be solvated orhydrated. Suitable solvates include pharmaceutically acceptablesolvates, such as hydrates, and further include both stoichiometricsolvates and non-stoichiometric solvates.

“Subject” includes humans. The terms “human,” “patient” and “subject”are used interchangeably herein.

“Therapeutically effective amount” means the amount of a compound that,when administered to a subject for treating a disease, is sufficient toeffect such treatment for the disease. The “therapeutically effectiveamount” can vary depending on the compound, the disease and itsseverity, and the age, weight, etc., of the subject to be treated.

“Treating” or “treatment” of any disease or disorder refers, in oneembodiment, to ameliorating the disease or disorder (i.e., arresting orreducing the development of the disease or at least one of the clinicalsymptoms thereof). In another embodiment “treating” or “treatment”refers to ameliorating at least one physical parameter, which may not bediscernible by the subject. In yet another embodiment, “treating” or“treatment” refers to modulating the disease or disorder, eitherphysically, (e.g., stabilization of a discernible symptom),physiologically, (e.g., stabilization of a physical parameter), or both.In yet another embodiment, “treating” or “treatment” refers to delayingthe onset of the disease or disorder, or even preventing the same.

It is also to be understood that compounds that have the same molecularformula but differ in the nature or sequence of bonding of their atomsor the arrangement of their atoms in space are termed “isomers”. Isomersthat differ in the arrangement of their atoms in space are termed“stereoisomers”.

Stereoisomers that are not mirror images of one another are termed“diastereomers” and those that are non-superimposable mirror images ofeach other are termed “enantiomers”. When a compound has an asymmetriccenter, for example, it is bonded to four different groups, a pair ofenantiomers is possible. An enantiomer can be characterized by theabsolute configuration of its asymmetric center and is described by theR- and S-sequencing rules of Cahn and Prelog, or by the manner in whichthe molecule rotates the plane of polarized light and designated asdextrorotatory or levorotatory (i.e., as (+) or (−)-isomersrespectively). A chiral compound can exist as either individualenantiomer or as a mixture thereof. A mixture containing equalproportions of the enantiomers is called a “racemic mixture”.

“Tautomers” refer to compounds that are interchangeable forms of aparticular compound structure, and that vary in the displacement ofhydrogen atoms and electrons. Thus, two structures may be in equilibriumthrough the movement of π electrons and an atom (usually H). Forexample, enols and ketones are tautomers because they are rapidlyinterconverted by treatment with either acid or base. Another example oftautomerism is the aci- and nitro- forms of phenylnitromethane, that arelikewise formed by treatment with acid or base. Representative enol—ketostructures and equilibrium are illustrated below:

Tautomeric forms may be relevant to the attainment of the optimalchemical reactivity and biological activity of a compound of interest.

The compounds of this invention may possess one or more asymmetriccenters; such compounds can therefore be produced as individual (R)— or(S)— stereoisomers or as mixtures thereof. Unless indicated otherwise,the description or naming of a particular compound in the specificationand claims is intended to include both individual enantiomers andmixtures, racemic or otherwise, thereof. The methods for thedetermination of stereochemistry and the separation of stereoisomers arewell-known in the art.

An “isotopic variant” refers to a compound as provided herein thatcontains unnatural proportions of isotopes at one or more of the atomsthat constitute such compounds. For example, in certain embodiments, an“isotopic variant” of a compound can contain one or more radioactiveisotopes such as tritium (³H), iodine-125 (¹²⁵I), carbon-14 (¹⁴C), andso forth. In some embodiments, an “isotopic variant” of a compound canbe a stable form, that is, non-radioactive, for example containing oneor more isotopes such as deuterium (²H), carbon-13 (¹³C), nitrogen-15(¹⁵N), and so forth. It will be understood that, in a compound asprovided herein, any hydrogen can be ²H, for example, or any carbon canbe ¹³C, as another example, or any nitrogen can be ¹⁵N, as anotherexample, and so forth, where feasible according to the judgment of oneof skill.

All isotopic variants of the compounds provided herein, radioactive ornot, are intended to be encompassed with the scope of the invention.

The Compounds

In certain aspects, the present invention provides fused heterocycliccompounds useful for preventing and/or treating a broad range ofconditions, among them, arthritis, Parkinson's disease, Alzheimer'sdisease, stroke, uveitis, asthma, myocardial infarction, the treatmentand prophylaxis of pain syndromes (acute and chronic or neuropathic),traumatic brain injury, acute spinal cord injury, neurodegenerativedisorders, alopecia (hair loss), inflammatory bowel disease andautoimmune disorders or conditions in mammals.

In one aspect, the present invention provides fused heterocycliccompounds according to formula 1:

wherein

A and B are independently selected from CR^(2′)R^(2′), CO, and CS;

Y is CR^(2′)R^(2′);

W is selected from CR⁴ and N;

Z is selected from O and NR²;

L is a bond, substituted or unsubstituted alkylene, or substituted orunsubstituted heteroalkylene;

R¹ is a substituted a unsubstituted carbocyclic group or a substitutedor unsubstituted heterocyclic group;

R² is selected from hydrogen, alkyl, cycloalkyl, aryl and aralkyl;

each R^(2′) is selected from hydrogen, substituted or unsubstitutedC₁-C₆ alkyl, substituted or unsubstituted C₃-C₈ cycloalkyl, substitutedor unsubstituted aryl and substituted or unsubstituted aralkyl;

R³ is a substituted or unsubstituted carbocyclic group or a substitutedor unsubstituted heterocyclic group;

R⁴ is selected from H, substituted or unsubstituted alkyl, substitutedor unsubstituted acyl, substituted or unsubstituted acylamino,substituted or unsubstituted alkylamino, substituted or unsubstitutedalkythio, substituted or unsubstituted alkoxy, substituted orunsubstituted alkoxycarbonyl, substituted or unsubstitutedalkylarylamino, substituted or unsubstituted arylalkyloxy, substitutedor unsubstituted amino, substituted or unsubstituted aryl, substitutedor unsubstituted arylalkyl, substituted or unsubstituted sulfoxide,substituted or unsubstituted sulfone, substituted or unsubstitutedsulfanyl, substituted or unsubstituted aminosulfonyl, substituted orunsubstituted arylsulfonyl, sulfuric acid, sulfuric acid ester,substituted or unsubstituted dihydroxyphosphoryl, substituted orunsubstituted aminodihydroxyphosphoryl, azido, substituted orunsubstituted carbamoyl, carboxyl, cyano, substituted or unsubstitutedcycloalkyl, substituted or unsubstituted cycloheteroalkyl, substitutedor unsubstituted dialkylamino, halo, heteroaryloxy, substituted orunsubstituted heteroaryl, substituted or unsubstituted heteroalkyl,hydroxy, nitro, and thio; and

R^(4′) is selected from R⁴ and -Z′-L′-R⁴, wherein Z′ is a bond, NR^(2′),O, S, SO, SO₂, COO, or CONR^(2′) and L′ is (C₁-C₆)alkylene;

or a pharmaceutically acceptable salt, solvate, prodrug, stereoisomer,tautomer or isotopic variant thereof.

In one aspect, a compound having formula 1a is provided:

wherein

A is selected from CR^(2′)R^(2′), CO, and CS;

each of B and Y is CR^(2′);

W is selected from CR⁴ and N;

Z is selected from O and NR²;

L is a bond, substituted or unsubstituted alkylene, or substituted orunsubstituted heteroalkylene;

R¹ is a substituted a unsubstituted carbocyclic group or a substitutedor unsubstituted heterocyclic group;

R² is selected from hydrogen, alkyl, cycloalkyl, aryl and aralkyl;

each of R^(2′) is selected from hydrogen, substituted or unsubstitutedC₁-C₆ alkyl, substituted or unsubstituted C₃-C₈ cycloalkyl, substitutedor unsubstituted aryl and substituted or unsubstituted aralkyl;

R³ is a substituted or unsubstituted carbocyclic group or a substitutedor unsubstituted heterocyclic group;

R⁴ is selected from H, substituted or unsubstituted alkyl, substitutedor unsubstituted acyl, substituted or unsubstituted acylamino,substituted or unsubstituted alkylamino, substituted or unsubstitutedalkythio, substituted or unsubstituted alkoxy, substituted orunsubstituted alkoxycarbonyl, substituted or unsubstitutedalkylarylamino, substituted or unsubstituted arylalkyloxy, substitutedor unsubstituted amino, substituted or unsubstituted aryl, substitutedor unsubstituted arylalkyl, substituted or unsubstituted sulfoxide,substituted or unsubstituted sulfone, substituted or unsubstitutedsulfanyl, substituted or unsubstituted aminosulfonyl, substituted orunsubstituted arylsulfonyl, sulfuric acid, sulfuric acid ester,substituted or unsubstituted dihydroxyphosphoryl, substituted orunsubstituted aminodihydroxyphosphoryl, azido, substituted orunsubstituted carbamoyl, carboxyl, cyano, substituted or unsubstitutedcycloalkyl, substituted or unsubstituted cycloheteroalkyl, substitutedor unsubstituted dialkylamino, halo, heteroaryloxy, substituted orunsubstituted heteroaryl, substituted or unsubstituted heteroalkyl,hydroxy, nitro, and thio; and

R^(4′) is selected from R⁴ and -Z′-L′-R⁴, wherein Z′ is a bond, NR^(2′),O, S, SO, SO₂, COO, or CONR^(2′) and L′ is (C₁-C₆)alkylene;

or a pharmaceutically acceptable salt, solvate, prodrug, stereoisomer,tautomer or isotopic variant thereof.

With regard to compounds of formula 1, in certain embodiments, A, B andY independently represent CR^(2′)R^(2′). More suitably, with respect toformula 1, each of A, B and Y independently represent CH₂.

With respect to formula 1a, in certain embodiments, A represents CH₂ andeach of B and Y independently represent CH.

With regard to compounds of formula 1 and 1a, in some embodiments, Z isO or NH. In one embodiment Z is O. In yet another and preferredembodiment Z is NH.

In some embodiments, L is a bond.

In certain embodiments, L is C₁-C₉ alkylene or C₁-C₉ heteroalkylene

In yet other embodiments, L is C₂-C₅ alkylene or C₂-C₅ heteroalkylene.In some embodiments, L is C₂-C₅ heteroalkylene containing two to fourcarbon atoms and a heteroatom selected from O, N, or S. Suitably theheteroatom is S.

In some embodiments, L is selected from —CH₂—, —(CH₂)₂—, —(CH₂)₃—,—(CH₂)₄—, —CH(CH₃)CH₂—, —(CH₂)₂SCH₂—, —(CH₂)₂—SO₂CH₂—, —CH(CH₂CH₃)CH₂OCH₂—, —CH₂CHF—, —CH₂CF₂—, —CH₂CH(OH)— and —CH₂CO—.

In a preferred embodiment, L is a bond, or is a —(CH₂)₂SCH₂— group.

With regard to formula 1, in certain embodiments, the compound isselected from the group consisting of6-(3-chloropyridin-2-yl)-N-(4-(difluoromethoxy)phenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine;6-(3-chloropyridin-2-yl)-5,6,7,8-tetrahydro-N-phenylpyrido[4,3-d]pyrimidin-4-amine;6-(3-chloropyridin-2-yl)-N-(4-fluorophenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine;6-(3-chloropyridin-2-yl)-N-(6-(trifluoromethyl)pyridin-3-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine;N-(6-(trifluoromethyl)pyridin-3-yl)-5,6,7,8-tetrahydro-6-(3-(methylsulfonyl)pyridin-2-yl)pyrido[4,3-d]pyrimidin-4-amine;6-(3-chloropyridin-2-yl)-5,6,7,8-tetrahydro-N-(4-(trifluoromethylsulfonyl)phenyl)pyrido[4,3-d]pyrimidin-4-amine;5,6,7,8-tetrahydro-6-(3-(methylsulfonyl)pyridin-2-yl)-N-(4-(trifluoromethylsulfonyl)phenyl)pyrido[4,3-d]pyrimidin-4-amine;5,6,7,8-tetrahydro-N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-6-m-tolylpyrido[4,3-d]pyrimidin-4-amine;N-(4-(trifluoromethyl)phenyl)-5,6,7,8-tetrahydro-6-phenylpyrido[4,3-d]pyrimidin-4-amine;N-(4-(trifluoromethyl)phenyl)-5,6,7,8-tetrahydro-6-o-tolylpyrido[4,3-d]pyrimidin-4-amine;N-(4-(trifluoromethyl)phenyl)-5,6,7,8-tetrahydro-6-m-tolylpyrido[4,3-d]pyrimidin-4-amine;andN-(4-(trifluoromethyl)phenyl)-5,6,7,8-tetrahydro-6-p-tolylpyrido[4,3-d]pyrimidin-4-amine.

With regard to formula 1, in certain embodiments where L is a bond, thecompound is not6-(3-chloropyridin-2-yl)-N-(4-(difluoromethoxy)phenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine;6-(3-chloropyridin-2-yl)-5,6,7,8-tetrahydro-N-phenylpyrido[4,3-d]pyrimidin-4-amine;6-(3-chloropyridin-2-yl)-N-(4-fluorophenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine;6-(3-chloropyridin-2-yl)-N-(6-(trifluoromethyl)pyridin-3-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine;N-(6-(trifluoromethyl)pyridin-3-yl)-5,6,7,8-tetrahydro-6-(3-(methylsulfonyl)pyridin-2-yl)pyrido[4,3-d]pyrimidin-4-amine;6-(3-chloropyridin-2-yl)-5,6,7,8-tetrahydro-N-(4-(trifluoromethylsulfonyl)phenyl)pyrido[4,3-d]pyrimidin-4-amine;5,6,7,8-tetrahydro-6-(3-(methylsulfonyl)pyridin-2-yl)-N-(4-(trifluoromethylsulfonyl)phenyl)pyrido[4,3-d]pyrimidin-4-amine;5,6,7,8-tetrahydro-N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-6-m-tolylpyrido[4,3-d]pyrimidin-4-amine;N-(4-(trifluoromethyl)phenyl)-5,6,7,8-tetrahydro-6-phenylpyrido[4,3-d]pyrimidin-4-amine;N-(4-(trifluoromethyl)phenyl)-5,6,7,8-tetrahydro-6-o-tolylpyrido[4,3-d]pyrimidin-4-amine;N-(4-(trifluoromethyl)phenyl)-5,6,7,8-tetrahydro-6-m-tolylpyrido[4,3-d]pyrimidin-4-amine;orN-(4-(trifluoromethyl)phenyl)-5,6,7,8-tetrahydro-6-p-tolylpyrido[4,3-d]pyrimidin-4-amine.

With regard to formula 1, in certain embodiments where L is a bond, thecompound is not:

3-chloro-7-cyclohexyl-1-(cyclohexylamino)-5,6,7,8-tetrahydro-2,7-naphthyridine-4-carbonitrile;

7-cyclohexyl-1-(cyclohexylamino)-5,6,7,8-tetrahydro-3-(1-piperidinyl)-2,7-naphthyridine-4-carbonitrile;or

7-cyclohexyl-1-(cyclohexylamino)-5,6,7,8-tetrahydro-3-(4-morpholinyl)-2,7-naphthyridine-4-carbonitrile.

With regard to compounds of formula 1 and 1a, in certain embodiments, Wis CR⁴. In some embodiments, W is N.

In certain embodiments, R¹ is a carbocyclic group. Alternatively, R¹ isa heterocyclic group.

In some embodiments, R¹ is an aryl or heteroaryl group.

In certain other embodiments, R¹ is a cycloalkyl or cycloheteroalkylgroup.

In yet other embodiments, R¹ is selected from substituted orunsubstituted

In yet other embodiments, R¹ is selected from substituted orunsubstituted

wherein Y′ is selected form ), N, S, SO, SO₂, and NR^(2′).

In some embodiments, R¹ is selected from substituted or unsubstituted

In certain embodiments, R¹ is selected from substituted or unsubstituted

In other embodiments, R¹ is selected from substituted or unsubstituted

In yet other embodiments, R¹ is selected from substituted orunsubstituted

wherein Y′ is selected from CR^(2′), CR^(2′)R^(2′), N, O, S, SO, SO₂ andNR^(2′).

In some embodiments, R¹ is selected from substituted or unsubstituted

In some embodiments, R¹ is selected from substituted or unsubstituted

In preferred embodiments, R¹ is selected from

Suitably, the substituent on N is H or substituted or unsubstitutedalkyl, where feasible.

With regard to formula 1 and 1a, in certain embodiments, R² is selectedfrom hydrogen, C₁-C₆ alkyl, C₃-C₈ cycloalkyl, aryl and aralkyl. Incertain embodiments, R² is selected from hydrogen, C₁-C₆ alkyl, andC₃-C₈ cycloalkyl.

With regard to formula 1 and 1a, in certain embodiments, each R^(2′) isindependently selected from hydrogen, and substituted or unsubstitutedC₁-C₆ alkyl. In preferred embodiments, R^(2′) is hydrogen.

In certain embodiments, R³ is a carbocyclic group. In some embodiments,R³ is a heterocyclic group. In certain embodiments, R³ is an aryl orheteroaryl. In some embodiments, R³ is an aryl.

In some embodiments, R³ is selected from substituted or unsubstitutedaryl, substituted or unsubstituted heteroaryl, substituted orunsubstituted cycloalkyl, substituted or unsubstituted cycloheteroalkyl,substituted or unsubstituted cycloalkenyl, substituted or unsubstitutedcycloheteroalkenyl, substituted or unsubstituted bicycloalkyl,substituted or unsubstituted bicycloheteroalkyl, substituted orunsubstituted bicycloalkenyl, substituted or unsubstitutedbicycloheteroalkenyl, substituted or unsubstituted bicycloaryl, andsubstituted or unsubstituted bicycloheteroaryl.

In some embodiments, R³ is a phenyl. In certain embodiments, R³ is asubstituted phenyl.

In some embodiments, R³ is a mono-substitued phenyl.

In other embodiments, R³ is a di-substituted phenyl.

In certain embodiments, R³ is a substituted phenyl where the substituenton the phenyl is selected from halo, amido, alkyl, alkoxy, sulfonyl,sulfonamidyl, haloalkyl and trihaloalkyl. In preferred embodiments, thesubstitution on the R³ phenyl is selected from Cl, F, CF₃, Me, OMe,SO₂R^(2′), NR^(2′)R^(2′), and SO₂NR^(2′)R^(2′). In more preferredembodiments, the substitution on the R³ phenyl is selected from Cl, Meand SO₂Me. In the most preferred embodiments, the substitution on the R³phenyl is Cl.

In embodiments where R³ is a substituted phenyl, one or moresubstitutuents are on the phenyl at the 2 (ortho), 3 (meta) and/or 4(para) position relative to the carbon attached to the nitrogen atom inthe fused heterocyclic scaffold in formula 1 or 1a. In certainembodiments, R³ is a substituted phenyl, where a substituent is on thephenyl at the 2 (ortho), 3 (meta) and/or 4 (para) position. In morepreferred embodiments, the substitution on the R³ phenyl is at the 2 or4 position. In the most preferred embodiments, the substitution on theR³ phenyl is at the 2 position.

In some embodiments, R³ is a heteroaryl.

In certain embodiments, R³ is a substituted pyridyl or pyrimidine group.

In some embodiments, R³ is a substituted pyridyl.

In some embodiments, R³ is a substituted pyrid-2-yl. In certainembodiments, the R³ pyrid-2-yl is di-substituted. In preferredembodiments, the R³ pyrid-2-yl is mono substituted.

In other embodiments, the substituent on the R³ pyrid-2-yl is selectedfrom halo, amido, alkyl, alkoxy, sulfonyl, sulfonamidyl, haloalkyl andtrihaloalkyl.

In preferred embodiments, the substitution on the R³ pyrid-2-yl isselected from Cl, F, CF₃, Me, OMe, SO₂R^(2′), NR^(2′)R^(2′), andSO₂NR^(2′)R^(2′). In more preferred embodiments, the substitution on R³pyrid-2-yl is selected from Cl, Me and SO₂Me. In the most preferredembodiments, the substitution on R³ pyrid-2-yl is Cl or Me.

In some embodiments, the substitution on the R³ pyrid-2-yl is at the 3,4 or 5 position. In more preferred embodiments, the substitution on theR³ pyrid-2-yl is at the 3 or 5 position. In the most preferredembodiments, the substitution on the R³ pyrid-2-yl is at the 3-position.

In the most preferred embodiments, R³ is 3-chloropyrid-2-yl or5-methylpyrid-2-yl.

In some embodiments, R¹ or R³ are selected from

wherein subscript n′ is selected from 1-5 and each of R⁵ isindependently selected from hydrogen, substituted or unsubstitutedalkyl, substituted or unsubstituted acyl, substituted or unsubstitutedacylamino, substituted or unsubstituted alkylamino, substituted orunsubstituted alkythio, substituted or unsubstituted alkoxy, aryloxy,alkoxycarbonyl, substituted alkoxycarbonyl, substituted or unsubstitutedalkylarylamino, arylalkyloxy, substituted arylalkyloxy, amino, aryl,substituted aryl, arylalkyl, substituted or unsubstituted sulfoxide,substituted or unsubstituted sulfone, substituted or unsubstitutedsulfanyl, substituted or unsubstituted aminosulfonyl, substituted orunsubstituted arylsulfonyl, sulfuric acid, sulfuric acid ester,substituted or unsubstituted dihydroxyphosphoryl, substituted orunsubstituted aminodihydroxyphosphoryl, azido, substituted orunsubstituted carbamoyl, carboxyl, cyano, substituted or unsubstitutedcycloalkyl, substituted or unsubstituted cycloheteroalkyl, substitutedor unsubstituted dialkylamino, halo, heteroaryloxy, substituted orunsubstituted heteroaryl, substituted or unsubstituted heteroalkyl,hydroxy, nitro, and thio.

With regard to formula 1 and 1a, in certain embodiments, W is CR⁴, whereR⁴ is as defined above in formula 1.

In some embodiments, W is CR⁴, where R⁴ is selected from H, alkyl andhalo.

In preferred embodiments, W is CR⁴, and R⁴ is H.

In certain embodiments R^(4′) is selected from H, substituted orunsubstituted alkyl, substituted or unsubstituted acyl, substituted orunsubstituted acylamino, substituted or unsubstituted alkylamino,substituted or unsubstituted alkythio, substituted or unsubstitutedalkoxy, substituted or unsubstituted alkoxycarbonyl, substituted orunsubstituted alkylarylamino, substituted or unsubstituted arylalkyloxy,substituted or unsubstituted amino, substituted or unsubstituted aryl,substituted or unsubstituted arylalkyl, substituted or unsubstitutedsulfoxide, substituted or unsubstituted sulfone, substituted orunsubstituted sulfanyl, substituted or unsubstituted aminosulfonyl,substituted or unsubstituted arylsulfonyl, sulfuric acid, sulfuric acidester, substituted or unsubstituted dihydroxyphosphoryl, substituted orunsubstituted aminodihydroxyphosphoryl, azido, substituted orunsubstituted carbamoyl, carboxyl, cyano, substituted or unsubstitutedcycloalkyl, substituted or unsubstituted cycloheteroalkyl, substitutedor unsubstituted dialkylamino, halo, heteroaryloxy, substituted orunsubstituted heteroaryl, substituted or unsubstituted heteroalkyl,hydroxy, nitro, and thio.

In some embodiments, R^(4′) is selected from H, halo, alkyl, CF₃, cyano,OR²′, SR²′, COOR²′, and CONR²′R²′.

In yet other embodiments, R^(4′) is selected from Et, Cl, Me, n-Bu,i-Pr, n-Pr, CH₂F, NHEt, OEt, CO₂H, SO₂Me, CONHCH₂Ph, SMe, SEt, S-n-Pr,SCH₂Ph, S-i-Pr, SCH₂COMe, SCH₂COOMe, SCH₂CONHMe, SCH₂CF₃, SCH₂CN,SCH₂CONH₂, S(CH₂)₂OH, S(CH₂)₂OMe, S(CH₂)₂COOMe, S(CH₂)₂NHCOMe,SCH₂CH(OH)CH₂OH, SCH₂CH(OH)CH₃, S(CH₂)₂F, S(CH₂)₃OH, and SCH₂C(Me)₂OH.In one preferred embodiment, R^(4′) is S(CH₂)₂OH.

In yet other embodiments, R^(4′) is selected from OMe, OEt, 0-n-Pr,OCH₂Ph, O-i-Pr, OCH₂COMe, OCH₂COOMe, OCH₂CONHMe, OCH₂CF₃, OCH₂CN,OCH₂CONH₂, O(CH₂)₂OH, O(CH₂)₂OMe, O(CH₂)₂COOMe, O(CH₂)₂NHCOMe,OCH₂CH(OH)CH₂OH, OCH₂CH(OH)CH₃, O(CH₂)₂F, O(CH₂)₃OH, and OCH₂C(Me)₂OH.In one preferred embodiment, R^(4′) is O(CH₂)₂OH.

In yet other embodiments, R^(4′) is selected from CH₂Me, CH₂Et,CH₂-n-Pr, CH₂CH₂Ph, CH₂-i-Pr, CH₂CH₂COMe, CH₂CH₂COOMe, CH₂CH₂CONHMe,CH₂CH₂CF₃, CH₂CH₂CN, CH₂CH₂CONH₂, CH₂(CH₂)₂OH, CH₂(CH₂)₂OMe,CH₂(CH₂)₂COOMe, CH₂(CH₂)₂NHCOMe, CH₂CH₂CH(OH)CH₂OH, CH₂CH₂CH(OH)CH₃,CH₂(CH₂)₂F, CH₂(CH₂)₃OH, and CH₂CH₂C(Me)₂OH. In one preferredembodiment, R^(4′) is CH₂(CH₂)₂OH.

In other embodiments, R^(4′) is a group -Z′-L′-R⁴.

In certain embodiments, when R^(4′) is a group -Z′-L′-R⁴, Z′ is selectedfrom a bond, NR²′, O, S, SO, SO₂, and CONH. In further embodiments, Z′is a bond, O or S. In yet further embodiments, Z′ is O or S. In apreferred embodiment, Z′ is S.

In certain embodiments when R^(4′) is a group -Z′-L′-R⁴, L′ is asubstituted or unsubstituted alkylene chain or heteroalkylene chain. Infurther embodiments, L′ is a substituted or unsubstituted alkylene chainof 1-9 C atoms in length. In preferred embodiments, L′ is selected from—(CH₂)₂—, —(CH₂)₃—, —(CH₂)₄—, —CH(CH₃)CH₂—, —CH(CH₂CH₃)CH₂OCH₂—,—CH₂CHF—, —CH₂CF₂—, and —CH₂CH(OH)—. In more preferred embodiments, L′is selected from —(CH₂)₂—, —CH(CH₃)CH₂—, —CH₂CHF—, —CH₂CF₂—, and—CH₂CH(OH)—. In one preferred embodiment, L′ is —(CH₂)₂—.

In certain embodiments when R^(4′) is a group -Z′-L′-R⁴, R⁴ is selectedfrom H, halo, alkoxy, CF₃, COOR^(2′), COR^(2′), CONR^(2′)R^(2′), OH, CNand substituted or unsubstituted aryl. In further embodiments, R⁴ isselected from halo, OH, CF₃, COMe and COOMe. In preferred embodiments,R⁴ is selected from halo, OH, CF₃, and COMe. In more preferredembodiments, R⁴ is selected from halo and OH. In one preferredembodiment, R⁴ is OH.

A, B and Y can, for example, all represent CH₂. Alternatively, A canrepresent CO, and B and Y represent CH₂. Alternatively, B can representCO, and A and Y represent CH₂.

Among the compounds described above by formula 1, in certain preferableembodiments, R³ is a 6 membered aryl or heteroaryl ring.

With regard to formula 1, in certain embodiments, a compound is providedhaving formula 2:

wherein W, Z, L, R¹, R³ and R^(4′) are as defined above in formula 1, ora pharmaceutically acceptable salt, solvate, prodrug, stereoisomer,tautomer or isotopic variant thereof.

With regard to formula 2, in some embodiments, W is selected from CR⁴and N.

In some embodiments, Z is NH.

In some embodiements, R³ is selected from substituted or unsubstitutedaryl, substituted or unsubstituted heteroaryl, substituted orunsubstituted cycloalkyl, substituted or unsubstituted cycloheteroalkyl,cycloalkenyl, substituted or unsubstituted cycloheteroalkenyl,substituted or unsubstituted bicycloalkyl, substituted or unsubstitutedbicycloheteroalkyl, substituted or unsubstituted bicycloalkenyl,substituted or unsubstituted bicycloheteroalkenyl, substituted orunsubstituted bicycloaryl, and substituted or unsubstitutedbicycloheteroaryl.

In some embodiments, R^(4′) is H.

In some embodiments, the compound according to formula 1 can bedescribed by formula 3:

wherein

X is N or CR⁴;

L is a bond, substituted or unsubstituted alkylene, or substituted orunsubstituted heteroalkylene;

R¹ is a substituted a unsubstituted carbocyclic group or a substitutedor unsubstituted heterocyclic group;

each R⁴ is independently selected from H, substituted or unsubstitutedalkyl, substituted or unsubstituted acyl, substituted or unsubstitutedacylamino, substituted or unsubstituted alkylamino, substituted orunsubstituted alkythio, substituted or unsubstituted alkoxy, substitutedor unsubstituted alkoxycarbonyl, substituted or unsubstitutedalkylarylamino, substituted or unsubstituted arylalkyloxy, substitutedor unsubstituted amino, substituted or unsubstituted aryl, substitutedor unsubstituted arylalkyl, substituted or unsubstituted sulfoxide,substituted or unsubstituted sulfone, substituted or unsubstitutedsulfanyl, substituted or unsubstituted aminosulfonyl, substituted orunsubstituted arylsulfonyl, sulfuric acid, sulfuric acid ester,substituted or unsubstituted dihydroxyphosphoryl, substituted orunsubstituted aminodihydroxyphosphoryl, azido, substituted orunsubstituted carbamoyl, carboxyl, cyano, substituted or unsubstitutedcycloalkyl, substituted or unsubstituted cycloheteroalkyl, substitutedor unsubstituted dialkylamino, halo, heteroaryloxy, substituted orunsubstituted heteroaryl, substituted or unsubstituted heteroalkyl,hydroxy, nitro, and thio;

R^(4′) is selected from R⁴ and a group -Z′-L′-R⁴, wherein Z′ is a bond,NR²′, O, S, SO, SO₂, COO, or CONR^(2′); and L′ is substituted orunsubstituted C₁-C₆ alkylene; and

subscript m is selected from 0-4.

In certain embodiments, subscript m is selected from 0 to 3.

In some embodiments, the compounds according to formula 1a can bedescribed by formula 4:

wherein

X is N or CR⁴;

L is a bond or substituted or unsubstituted alkylene or heteroalkylenechain;

R¹ is substituted and unsubstituted carbocyclic or heterocyclic group;

each R⁴ is independently selected from H, alkyl, substituted alkyl,acyl, substituted acyl, substituted or unsubstituted acylamino,substituted or unsubstituted alkylamino, substituted or unsubstitutedalkythio, substituted or unsubstituted alkoxy, alkoxycarbonyl,substituted alkoxycarbonyl, substituted or unsubstituted alkylarylamino,arylalkyloxy, substituted arylalkyloxy, amino, aryl, substituted aryl,arylalkyl, substituted or unsubstituted sulfoxide, substituted orunsubstituted sulfone, substituted or unsubstituted sulfanyl,substituted or unsubstituted aminosulfonyl, substituted or unsubstitutedarylsulfonyl, sulfuric acid, sulfuric acid ester, substituted orunsubstituted dihydroxyphosphoryl, substituted or unsubstitutedaminodihydroxyphosphoryl, azido, substituted or unsubstituted carbamoyl,carboxyl, cyano, substituted or unsubstituted cycloalkyl, substituted orunsubstituted cycloheteroalkyl, substituted or unsubstituteddialkylamino, halo, heteroaryloxy, substituted or unsubstitutedheteroaryl, substituted or unsubstituted heteroalkyl, hydroxy, nitro,and thio;

R^(4′) is selected from R⁴ and a group -Z′-L′-R⁴, wherein Z′ is a bond,NR²′, O, S, SO, SO₂, COO, or CONR^(2′); L′ is substituted orunsubstituted C₁-C₆ alkylene chain and R^(4″) is R⁴; and

subscript m is selected from 0-4;

or a pharmaceutically acceptable salt, solvate, prodrug, stereoisomer,tautomer, or isotopic variant thereof.

In some embodiments, subscript m is selected from 0, 1, 2 or 3.

It will be understood that the compounds provided herein, for example,as provided in any formula, including formulas 1-10, can be in the formof a pharmaceutically acceptable salt, solvate, prodrug, stereoisomer,tautomer, or istopic variant.

In certain embodiments, compounds are provided having any one offormulas 5-10:

wherein R⁴ is selected from Cl, F, Me, iso-Pr, OMe, OCF₃, SO₂CF₃, SO₂Me,and SO₂NMe₂, and L, R¹ and R^(4′) are as defined above.

In some embodiments, L-R¹ can, for example, be selected from

andsubstitued versions thereof, where the phenyl is substituted with 1, 2or 3 halo, CF₃, or SMe groups.

In certain embodiments, L-R¹ is selected from substituted orunsubstituted

In some embodiements, L-R¹ is selected from substituted or unsubstituted

wherein the substitutent on N is H or substituted or unsubstitutedalkyl.

In certain embodiments, L-R¹ is selected from substituted orunsubstituted

wherein

R^(1″) is H, alkyl, or a group represented by—(CR^(2′)R^(2′))_(n)—R^(3″);

each R^(2′) is selected from hydrogen, substituted or unsubstitutedC₁-C₆ alkyl, substituted or unsubstituted C₃-C₈ cycloalkyl, substitutedor unsubstituted aryl and substituted or unsubstituted aralkyl;

R^(3″) is hydrogen, a hetero substituent, aryl, heteroaryl, heteroalkyl,cycloalkyl, cycloheteroalkyl, cycloalkenyl, cycloheteroalkenyl,bicycloalkyl, bicycloheteroalkyl, bicycloalkenyl, bicycloheteroalkenyl,bicycloaryl, or bicycloheteroaryl ring; and

subscript n is selected from 2-5.

In preferred embodiments, each R^(2′) is H; subscript n is 2-4 andR^(3″) is substituted or unsubstituted cycloalkyl, cycloheteroalkyl,aryl or heteroaryl.

R^(3″) can, for example, be substituted or unsubstituted

and where R² is H or alkyl.

R^(3″) can, for example, be a hetero substitutent and there is apreference for the heterosubstituent to be COOH, SO₂Me, SMe, OH, OEt,OMe, NEt₂, halo, NHSO₂Me, CONH₂, CONMe₂, SO₂NH₂, and SO₂NMe₂.

Additional embodiments within the scope of the present invention are setforth in non-limiting fashion elsewhere herein and in the examples. Itshould be understood that these examples are for illustrative purposesonly and are not to be construed as limiting this invention in anymanner.

In certain aspects, the present invention provides prodrugs andderivatives of the compounds according to the formulae above. Prodrugsare derivatives of the compounds of the invention, which havemetabolically cleavable groups and become by solvolysis or underphysiological conditions the compounds of the invention, which arepharmaceutically active, in vivo. Such examples include, but are notlimited to, choline ester derivatives and the like, N-alkylmorpholineesters and the like.

Certain compounds of this invention have activity in both their acid andacid derivative forms, but the acid sensitive form often offersadvantages of solubility, tissue compatibility, or delayed release inthe mammalian organism (see, Bundgard, H., Design of Prodrugs, pp. 7-9,21-24, Elsevier, Amsterdam 1985). Prodrugs include acid derivatives wellknow to practitioners of the art, such as, for example, esters preparedby reaction of the parent acid with a suitable alcohol, or amidesprepared by reaction of the parent acid compound with a substituted orunsubstituted amine, or acid anhydrides, or mixed anhydrides. Simplealiphatic or aromatic esters, amides and anhydrides derived from acidicgroups pendant on the compounds of this invention are preferredprodrugs. In some cases it is desirable to prepare double ester typeprodrugs such as (acyloxy)alkyl esters or((alkoxycarbonyl)oxy)alkylesters. Preferred are the C₁ to C₈ alkyl,C₂-C₈ alkenyl, aryl, C₇-C₁₂ substituted aryl, and C₇-C₁₂ arylalkylesters of the compounds of the invention.

Pharmaceutical Compositions

When employed as pharmaceuticals, the fused heterocyclic compounds ofthis invention are typically administered in the form of apharmaceutical composition. Such compositions can be prepared in amanner well known in the pharmaceutical art and comprise at least oneactive compound.

Generally, the compounds of this invention are administered in apharmaceutically effective amount. The amount of the compound actuallyadministered will typically be determined by a physician, in the lightof the relevant circumstances, including the condition to be treated,the chosen route of administration, the actual compound -administered,the age, weight, and response of the individual patient, the severity ofthe patient's symptoms, and the like.

The pharmaceutical compositions of this invention can be administered bya variety of routes including oral, rectal, transdermal, subcutaneous,intravenous, intramuscular, and intranasal. Depending on the intendedroute of delivery, the compounds of this invention are preferablyformulated as either injectable or oral compositions or as salves, aslotions or as patches all for transdermal administration.

The compositions for oral administration can take the form of bulkliquid solutions or suspensions, or bulk powders. More commonly,however, the compositions are presented in unit dosage forms tofacilitate accurate dosing. The term “unit dosage forms” refers tophysically discrete units suitable as unitary dosages for human subjectsand other mammals, each unit containing a predetermined quantity ofactive material calculated to produce the desired therapeutic effect, inassociation with a suitable pharmaceutical excipient. Typical unitdosage forms include prefilled, premeasured ampules or syringes of theliquid compositions or pills, tablets, capsules or the like in the caseof solid compositions. In such compositions, the furansulfonic acidcompound is usually a minor component (from about 0.1 to about 50% byweight or preferably from about 1 to about 40% by weight) with theremainder being various vehicles or carriers and processing aids helpfulfor forming the desired dosing form.

Liquid forms suitable for oral administration may include a suitableaqueous or nonaqueous vehicle with buffers, suspending and dispensingagents, colorants, flavors and the like. Solid forms may include, forexample, any of the following ingredients, or compounds of a similarnature: a binder such as microcrystalline cellulose, gum tragacanth orgelatin; an excipient such as starch or lactose, a disintegrating agentsuch as alginic acid, Primogel, or corn starch; a lubricant such asmagnesium stearate; a glidant such as colloidal silicon dioxide; asweetening agent such as sucrose or saccharin; or a flavoring agent suchas peppermint, methyl salicylate, or orange flavoring.

Injectable compositions are typically based upon injectable sterilesaline or phosphate-buffered saline or other injectable carriers knownin the art. As before, the active compound in such compositions istypically a minor component, often being from about 0.05 to 10% byweight with the remainder being the injectable carrier and the like.

Transdermal compositions are typically formulated as a topical ointmentor cream containing the active ingredient(s), generally in an amountranging from about 0.01 to about 20% by weight, preferably from about0.1 to about 20% by weight, preferably from about 0.1 to about 10% byweight, and more preferably from about 0.5 to about 15% by weight. Whenformulated as a ointment, the active ingredients will typically becombined with either a paraffinic or a water-miscible ointment base.Alternatively, the active ingredients may be formulated in a cream with,for example an oil-in-water cream base. Such transdermal formulationsare well-known in the art and generally include additional ingredientsto enhance the dermal penetration of stability of the active ingredientsor the formulation. All such known transdermal formulations andingredients are included within the scope of this invention.

The compounds of this invention can also be administered by atransdermal device. Accordingly, transdermal administration can beaccomplished using a patch either of the reservoir or porous membranetype, or of a solid matrix variety.

The above-described components for orally administrable, injectable ortopically administrable compositions are merely representative. Othermaterials as well as processing techniques and the like are set forth inPart 8 of Remington's Pharmaceutical Sciences, 17th edition, 1985, MackPublishing Company, Easton, Pa., which is incorporated herein byreference.

The compounds of this invention can also be administered in sustainedrelease forms or from sustained release drug delivery systems. Adescription of representative sustained release materials can be foundin Remington's Pharmaceutical Sciences.

The following formulation examples illustrate representativepharmaceutical compositions of this invention. The present invention,however, is not limited to the following pharmaceutical compositions.

Formulation 1—Tablets

A compound of formula I is admixed as a dry powder with a dry gelatinbinder in an approximate 1:2 weight ratio. A minor amount of magnesiumstearate is added as a lubricant. The mixture is formed into 240-270 mgtablets (80-90 mg of active compound per tablet) in a tablet press.

Formulation 2—Capsules

A compound of formula I is admixed as a dry powder with a starch diluentin an approximate 1:1 weight ratio. The mixture is filled into 250 mgcapsules (125 mg of active compound per capsule).

Formulation 3—Liquid

A compound of formula I (125 mg), sucrose (1.75 g) and xanthan gum (4mg) are blended, passed through a No. 10 mesh U.S. sieve, and then mixedwith a previously made solution of microcrystalline cellulose and sodiumcarboxymethyl cellulose (11:89, 50 mg) in water. Sodium benzoate (10mg), flavor, and color are diluted with water and added with stirring.Sufficient water is then added to produce a total volume of 5 mL.

Formulation 4—Tablets

The compound of formula I is admixed as a dry powder with a dry gelatinbinder in an approximate 1:2 weight ratio. A minor amount of magnesiumstearate is added as a lubricant. The mixture is formed into 450-900 mgtablets (150-300 mg of active compound) in a tablet press.

Formulation 5—Injection

The compound of formula I is dissolved or suspended in a bufferedsterile saline injectable aqueous medium to a concentration ofapproximately 5 mg/ml.

Formulation 6—Topical

Stearyl alcohol (250 g) and a white petrolatum (250 g) are melted atabout 75° C. and then a mixture of a compound of formula I (50 g)methylparaben (0.25 g), propylparaben (0.15 g), sodium lauryl sulfate(10 g), and propylene glycol (120 g) dissolved in water (about 370 g) isadded and the resulting mixture is stirred until it congeals.

Methods of Treatment

The present fused heterocyclic compounds are used as therapeutic agentsfor the treatment of conditions in mammals. Accordingly, the compoundsand pharmaceutical compositions of this invention find use astherapeutics for preventing and/or treating neurodegenerative,autoimmune and inflammatory conditions in mammals including humans.

In a method of treatment aspect, this invention provides a method oftreating a mammal susceptible to or afflicted with a conditionassociated with arthritis, asthma, myocardial infarction, inflammatorybowel disease and autoimmune disorders, which method comprisesadministering an effective amount of one or more of the pharmaceuticalcompositions just described.

In yet another method of treatment aspect, this invention provides amethod of treating a mammal susceptible to or afflicted with a conditionthat gives rise to pain responses or that relates to imbalances in themaintenance of basal activity of sensory nerves. The present compoundshave use as analgesics for the treatment of pain of various geneses oretiology, for example acute, inflammatory pain (such as pain associatedwith osteoarthritis and rheumatoid arthritis); various neuropathic painsyndromes (such as post-herpetic neuralgia, trigeminal neuralgia, reflexsympathetic dystrophy, diabetic neuropathy, Guillian Barre syndrome,fibromyalgia, phantom limb pain, post-masectomy pain, peripheralneuropathy, HIV neuropathy, and chemotherapy-induced and otheriatrogenic neuropathies); visceral pain, (such as that associated withgastroesophageal reflex disease, irritable bowel syndrome, inflammatorybowel disease, pancreatitis, and various gynecological and urologicaldisorders), dental pain and headache (such as migraine, cluster headacheand tension headache).

In additional method of treatment aspects, this invention providesmethods of treating a mammal susceptible to or afflicted withneurodegenerative diseases and disorders such as, for exampleParkinson's disease, Alzheimer's disease and multiple sclerosis;diseases and disorders which are mediated by or result inneuroinflammation such as, for example encephalitis; centrally-mediatedneuropsychiatric diseases and disorders such as, for example depressionmania, bipolar disease, anxiety, schizophrenia, eating disorders, sleepdisorders and cognition disorders; epilepsy and seizure disorders;prostate, bladder and bowel dysfunction such as, for example urinaryincontinence, urinary hesitancy, rectal hypersensitivity, fecalincontinence, benign prostatic hypertrophy and inflammatory boweldisease; respiratory and airway disease and disorders such as, forexample, allergic rhinitis, asthma and reactive airway disease andchronic obstructive pulmonary disease; diseases and disorders which aremediated by or result in inflammation such as, for example rheumatoidarthritis and osteoarthritis, myocardial infarction, various autoimmunediseases and disorders; itch/pruritus such as, for example psoriasis;obesity; lipid disorders; cancer; and renal disorders method comprisesadministering an effective condition-treating or condition-preventingamount of one or more of the pharmaceutical compositions just described.

As a further aspect of the invention there is provided the present fusedheterocyclic compounds for use as a pharmaceutical especially in thetreatment or prevention of the aforementioned conditions and diseases.We also provide the use of the present compounds in the manufacture of amedicament for the treatment or prevention of one of the aforementionedconditions and diseases.

Injection dose levels range from about 0.1 mg/kg/hour to at least 10mg/kg/hour, all for from about 1 to about 120 hours and especially 24 to96 hours. A preloading bolus of from about 0.1 mg/kg to about 10 mg/kgor more may also be administered to achieve adequate steady statelevels. The maximum total dose is not expected to exceed about 2 g/dayfor a 40 to 80 kg human patient.

For the prevention and/or treatment of long-term conditions, such asneurodegenerative and autoimmune conditions, the regimen for treatmentusually stretches over many months or years so oral dosing is preferredfor patient convenience and tolerance. With oral dosing, one to five andespecially two to four and typically three oral doses per day arerepresentative regimens. Using these dosing patterns, each dose providesfrom about 0.01 to about 20 mg/kg of the compound of the invention, withpreferred doses each providing from about 0.1 to about 10 mg/kg andespecially about 1 to about 5 mg/kg.

Transdermal doses are generally selected to provide similar or lowerblood levels than are achieved using injection doses.

When used to prevent the onset of a neurodegenerative, autoimmune orinflammatory condition, the compounds of this invention will beadministered to a patient at risk for developing the condition,typically on the advice and under the supervision of a physician, at thedosage levels described above. Patients at risk for developing aparticular condition generally include those that have a family historyof the condition, or those who have been identified by genetic testingor screening to be particularly susceptible to developing the condition.

The compounds of this invention can be administered as the sole activeagent or they can be administered in combination with other agents,including other active amines and derivatives.

General Synthetic Procedures

The fused heterocyclic compounds of this invention can be prepared fromreadily available starting materials using the following general methodsand procedures. See, e.g., FIG. 1 and Synthetic Schemes 1-10 below. Itwill be appreciated that where typical or preferred process conditions(i.e., reaction temperatures, times, mole ratios of reactants, solvents,pressures, etc.) are given, other process conditions can also be usedunless otherwise stated. Optimum reaction conditions may vary with theparticular reactants or solvent used, but such conditions can bedetermined by one skilled in the art by routine optimization procedures.

Additionally, as will be apparent to those skilled in the art,conventional protecting groups may be necessary to prevent certainfunctional groups from undergoing undesired reactions. The choice of asuitable protecting group for a particular functional group as well assuitable conditions for protection and deprotection are well known inthe art. For example, numerous protecting groups, and their introductionand removal, are described in T. W. Greene and P. G. M. Wuts, ProtectingGroups in Organic Synthesis, Second Edition, Wiley, N.Y., 1991, andreferences cited therein.

The compounds of this invention, for example, may be prepared by thereaction of a chloro derivative with an appropriately substituted amineand the product isolated and purified by known standard procedures. Suchprocedures include (but are not limited to) recrystallization, columnchromatography or HPLC. The following schemes are presented with detailsas to the preparation of representative fused heterocyclics that havebeen listed hereinabove. The compounds of the invention may be preparedfrom known or commercially available starting materials and reagents byone skilled in the art of organic synthesis.

Synthetic Scheme 1

VariousN-substituted-6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-aminederivatives are prepared using a general procedure described below.Accordingly, ethyl 1-benzyl-4-oxopiperidine-3-carboxylate hydrochlorideis reacted with formamidine acetate to yield6-benzyl-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(4aH)-one, which, inturn, is reacted with POCl₃ to afford the 4-chloro derivative. Theintermediate chloro derivative is then condensed with substitutedaniline or amine to give the desiredN-substituted-6-benzyl-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine.Debenzylation using standard procedures known in the art followed bynucleophilic displacement of an appropriate 2-halo-pyridine yields theappropriateN-substituted-6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine.As a representative example, synthesis ofN-(4-tert-butylphenyl)-6-(3-chloropyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amineis depicted in Scheme 1.

Synthetic Scheme 2

Conversely,N-substituted-6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-aminederivatives are prepared by first deprotecting the6-benzyl-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(4aH)-one andreacting the product with an appropriate 2-halo-pyridine to give the6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(4aH)-onewhich is reacted with POCl₃ followed by condensation with an appropriateaniline or amine to yield the appropriate the appropriateN-substituted-6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine.As a representative example, synthesis ofN-(4-tert-butylphenyl)-6-(3-chloropyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amineis depicted in Scheme 2.

Synthetic Scheme 3

The 2-substituted pyrido[4,3-d]pyrimidin-4-one derivatives are preparedusing the synthetic sequence given below. The intermediate6-benzyl-5,6,7,8-tetrahydro-2-(methylthio)pyrido[4,3-d]pyrimidin-4(3H)-oneis formed by reaction of ethyl 1-benzyl-3-oxopiperidine-4-carboxylatehydrochloride with thiourea. This intermediate methylthio derivative isthen subjected to synthetic sequence outlined above (Scheme 2) to givethe appropriateN-substituted-6-(pyridin-2-yl)-5,6,7,8-tetrahydro-2-(methylthio)pyrido[4,3-d]pyrimidin-4-aminederivative, which is oxidized to the corresponding sulfone derivativeand in turn reacted with an appropriate nucleophile to give theanalogous2-substituted-N-substituted-6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-aminederivative. As a representative example, synthesis ofN-(4-tert-butylphenyl)-6-(3-chloropyridin-2-yl)-5,6,7,8-tetrahydro-2-methoxypyrido[4,3-d]pyrimidin-4-amineis depicted in Scheme 3.

Synthetic Scheme 4

Conversely, 2-chloroacetamidine hydrochloride is reacted with anappropriate nucleophile to form an appropriate amidine derivative. Theamidine is reacted with ethyl 1-benzyl-4-oxopiperidine-3-carboxylatehydrochloride to afford the intermediate2-substituted-N-substituted-6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-aminederivative. This intermediate pyrido[4,3-d]pyrimidin-4-amine is thensubjected to the reaction sequence described in Scheme 2 to yieldappropriately 2-substitutedN-substituted-6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-aminederivative. As a representative example, synthesis ofN-(4-tert-butylphenyl)-6-(3-chloropyridin-2-yl)-5,6,7,8-tetrahydro-2-(morpholinomethyl)pyrido[4,3-d]pyrimidin-4-amine is depicted in Scheme4.

Synthetic Scheme 5

Appropriate N-arylsubstituted-5,6,7,8-tetrahydro-6-arylpyrido[4,3-d]pyrimidin-4-amine,obtained by following synthetic scheme 2, are prepared by the reactionof the correspondingN-substituted-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine with anappropriate aryl boronic acid in the presence of copper acetate andtriethylamine. As a representative example, preparation ofN-(4-(trifluoromethyl)phenyl)-5,6,7,8-tetrahydro-6-m-tolylpyrido[4,3-d]pyrimidin-4-amineis depicted in Scheme 5.

Synthetic Scheme 6

Appropriate6-(pyridin-2-yl)-5,6,7,8-tetrahydro-N-(1,2,3,4-tetrahydro-4,4-dimethyl-1-substituted)quinolin-7-yl)pyrido[4,3-d]pyrimidin-4-aminederivatives are prepared starting from1,2,3,4-tetrahydro-4,4-dimethyl-7-nitroquinoline. The nitroquinolinederivate is reacted with appropriate alkylating agent to give theN-substituted nitroquinoline, which is reduced using standard proceduresknown in the art to yield 7-aminoquinoline derivative. The resultingaminoquinoline derivated is then condensed with the appropriate4-chloro-6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine togive the desired6-(pyridin-2-yl)-5,6,7,8-tetrahydro-N-(1,2,3,4-tetrahydro-4,4-dimethyl-1-substituted)quinolin-7-yl)pyrido[4,3-d]pyrimidin-4-aminederivative. As a representative example, preparation of theN-morpholionethyl derivative is depicted in Scheme 6.

Synthetic Scheme 7

A similar sequence of reactions using substituted amidines, and setforth in the scheme presented below, gives rise to 2-substitutedproducts. For example, trifluoromethyl amidine can be employed in thesimilar sequence of reactions to afford 2-trifluoromethyl substitutedproducts.

Synthetic Scheme 8

Similarly, another sequence of reactions, as depicted in Scheme 8, usingsubstituted amidines can be employed to prepare 2-substitutedderivatives.

Synthetic Scheme 9: General Synthesis of4-Alkylamino-pyrido[4,3-d]pyrimidines

N-alkylsubstituted-6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-aminederivatives are prepared by first deprotecting the6-benzyl-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(4aH)-one andreacting the product with an appropriate 2-halo-pyridine to give the6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(4aH)-onewhich is reacted with POCl3 followed by condensation with an appropriatealkylamine to yield the appropriate the appropriateN-substituted-6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine.As a representative example, synthesis ofN-(alkyl)-6-(3-chloropyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amineis depicted in Scheme 9.

L=alkylene or heteroalkylene chain and R¹=substituted and unsubstitutedcarbocyclic or heterocyclic group.

Synthetic Scheme 10: General Synthesis of 2-Substitutedpyrido[4,3-d]pyrimidines

The 2-substituted pyrido[4,3-d]pyrimidin-4-one derivatives are preparedusing the synthetic sequence given below. The intermediateN-substituted-6-(pyridin-2-yl)-5,6,7,8-tetrahydro-2-(methylthio)pyrido[4,3-d]pyrimidin-4-amine,as prepared following the synthetic Scheme 3, is oxidized to thecorresponding sulfone derivative and in turn reacted with an appropriatenucleophile to give the analogous2-substituted-N-substituted-6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-aminederivative.

Nu=R^(4″)-L′-Z′⁻; R^(4″)=substituted and unsubstituted carbocyclic orheterocyclic group; L′=alkylene or heteroalkylene chain; and Z′⁻=S⁻, orO⁻.

Synthetic Scheme 11: General Synthesis of 6 substitiuted5,6,7,8-tetrahydro-6-(5-methylpyridin-2-yl)pyrido[4,3-d]pyrimidine

Various 6 substituted5,6,7,8-tetrahydro-6-(5-methylpyridin-2-yl)pyrido[4,3-d]pyrimidines areprepared using a general procedure shown above. Ethyl1-benzyl-4-oxopiperidine-3-carboxylate hydrochloride is reacted withformamidine acetate to yield6-benzyl-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(4aH)-one, which, inturn, is reduced to 5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(3H)-one.The intermediate coupled with 5 chloro 2 methyl pyridine to produce5,6,7,8-tetrahydro-6-(5-methylpyridin-2-yl)pyrido[4,3-d]pyrimidin-4(3H)-one.Chlorination of the resulting product using POCl₃ and displacement ofthe chloride using various benzylamines via microwave displacement willafford various 6 substitiuted5,6,7,8-tetrahydro-6-(5-methylpyridin-2-yl)pyrido[4,3-d]pyrimidines.

The following synthetic and biological examples are offered toillustrate this invention and are not to be construed in any way aslimiting the scope of this invention. In the examples below, alltemperatures are in degrees Celsius (unless otherwise indicated). Thesyntheses of these representative compounds are carried out inaccordance with the methods set forth above and using the appropriatereagents, starting materials, and purification methods known to thoseskilled in the art.

EXEMPLARY COMPOUNDS OF THE INVENTION

The following compounds have been prepared according to the methods ofthe invention. Corresponding compounds have been recited hereinabove andin the claims. Unless otherwise indicated, reactions in microwave werecarried out in Emrys Optimizer or Smith Creator microwave modelsmanufactured by Personal Chemistry, Inc.

Synthesis of Intermediates Intermediate 16-Benzyl-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(3H)-one

A mixture of ethyl 1-benzyl-4-oxopiperidine-3-carboxylate hydrochloride(50.0 g, 0.168 mol), formamidine acetate (16.2 g, 0.201 mol), 4.37 M ofsodium methoxide in methanol (190 mL) and methanol (200 mL, 5 mol) washeated to 85° C. for 16 hour in a 350 ml sealed reaction vessel. Themixture was allowed to cool and reduced in vacuo. The residue wasdissolved in 1N NaOH (150 ml) and poured over ice. Glacial acetic acidwas added to the mixture until the pH of the mixture was 7 and a tansolid precipitated out. the solid was filtered, washed with water andcold ether, and dried on high vacuum to yield the title compound as atan solid. (26.2 g, 61.4%).

MS: M+H=242.2.

¹H NMR (DMSO-d6): δ 2.29 (t, 5.8 Hz, 2H); 2.61 (t, 5.8 Hz, 2H); 3.26 (s,2H); 3.64 (s, 2H); 7.21-7.36 (m, 6H); 7.96 (s, 1H).

Intermediate 26-Benzyl-4-chloro-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine

A mixture of 6-benzyl-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(3H)-one(5.0 g, 0.02 mol), phosphoryl chloride (3.30 mL, 0.035 mol) andacetonitrile (80 mL) and DMF (catalytic amount) was heated to at 70° C.for 1 hour. The mixture was reduced in vacuo and the remaining blackresidue was taken up in dichloromethane (250 ml) and poured over ice.The mixture was carefully neutralized with the addition of solid sodiumbicarbonate. The layers were separated and the organic dried over sodiumsulfate and reduced in vacuo. The mixture was chromatographed using anethyl acetate:hexanes (0-100%) gradient on an isco flash chromatographysystem. The combined pure fractions were reduced in vacuo to yield thetitle compound as a yellow oil (3 g, 57.8%).

MS: M+H=260.

¹H NMR (DMSO-d6): δ 8.80 (s, 1H). 7.40-7.24 (m, 5H), 3.76 (s, 2H), 3.57(s, 2H), 2.92 (t, 2H), 2.80 (t, 2H).

EXAMPLES Compound 16-(3-Chloropyridin-2-yl)-5,6,7,8-tetrahydro-N-[(4-difluoromethoxy)phenyl]pyrido[4,3-d]pyrimidin-4-amine

A.6-Benzyl-5,6,7,8-tetrahydro-N-[(4-difluoromethoxy)phenyl]pyrido[4,3-d]pyrimidin-4-amine

6-Benzyl-4-chloro-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine (1.09 g,4.21 mmol) prepared as described above (Intermediate 2, 1.0 g, 3.86mmol)was dissolved in anhydrous acetonitrile (3 mL) and4-difluoromethoxyaniline was added (1.34 g, 8.42 mmol). The mixture washeated at 180° C. for 600 s in a microwave (Emrys Optimizer model,Personal Chemistry). The solvents were removed under vacuum to give thedesired product as a beige powder (1.3 g, 94.2%). The crude product wasused for the subsequent step.B.5,6,7,8-Tetrahydro-N-[(4-difluoromethoxy)phenyl]pyrido[4,3-d]pyrimidin-4-amine

6-Benzyl-5,6,7,8-tetrahydro-N-[(4-difluoromethoxy)phenyl]pyrido[4,3-d]pyrimidin-4-amine(1.012 g, 2.65 mmol) was dissolved in methanol (20 mL) and palladiumhydroxide (1.5 g, 20% wt) and ammonium formate (1.67 g, 26.46 mmol) wereadded. The mixture was heated at reflux for one hour and then 10 hoursat room temperature under nitrogen. The mixture was filtered throughcelite and the filtrate concentrated to afford a solid which was takenup in saturated sodium bicarbonate (100 ml). The aqueous was extractedwith ethyl acetate (3×100 ml). The organic layers were combined, washedwith brine, dried over sodium sulfate and concentrated to leaved a tansolid. The crude solid was purified by column chromatography using amethanol:methylene chloride (0-20%) gradient. The combined purefractions were reduced in vacuo to yield the title compound (0.201 g) asa yellow solid which was used directly in the next stepC.6-(3-Chloropyridin-2-yl)-5,6,7,8-tetrahydro-N-[(4-difluoromethoxy)phenyl]pyrido[4,3-d]pyrimidin-4-amine

5,6,7,8-Tetrahydro-N-[(4-difluoromethoxy)phenyl]pyrido[4,3-d]pyrimidin-4-amine(0.091 g, 0.31 mmol) was dissolved in a mixture ofdioxane/N,N-dimethylacetamide (4:1) (2 mL). To the mixture was added2,3-dichloropyridine (0.092 g, 0.62 mmol) and N,N-diisopropylethylamine(0.081 mL, 0.47 mmol). The mixture was heated at 170° C. in a microwave(Emrys Optimizer model, Personal Chemistry) for 10 h. The mixture wasallowed to cool to room temperature and poured into water (60 ml) andextracted with ethyl acetate (2×30 ml). The organic layers werecombined, dried over Na₂SO₄, filtered, and evaporated to give a brownresidue. The residue was purified using a gradient of ethylacetate:hexane (0-100%) to give the desired compound as an off-whitepowder (0.38 g).

Compound 2 6-(3-Chloropyridin-2-yl)-5,6,7,8-tetrahydro-N-phenylpyrido[4,3-d]pyrimidin-4-amine

A. 6-Benzyl-5,6,7,8-tetrahydro-N-phenylpyrido[4,3-d]pyrimidin-4-amine

6-Benzyl-4-chloro-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine(Intermediate 2, 1.0 g, 3.86 mmol) was dissolved in anhydrousacetonitrile (3 mL) and aniline was added (0.39 mL, 4.24 mmol). Themixture was heated at 180° C. for 600 s in a microwave (Emrys Optimizermodel, Personal Chemistry). The solvents were removed under vacuum togive the desired product as a beige powder (1.5 g, quant.). The crudeproduct was used as such for the subsequent step.

MS: M+H=317.B. 5,6,7,8-Tetrahydro-N-phenylpyrido[4,3-d]pyrimidin-4-amine

6-Benzyl-5,6,7,8-tetrahydro-N-phenylpyrido[4,3-d]pyrimidin-4-amine (1.5g, 3.8 mmol) was dissolved in methanol (25 mL) and palladium hydroxidewas added (1.5 g, 20% wt). The mixture was shaken on a Parr Shaker underH₂ (g) atmosphere (60 PSI) for 1 day. The mixture was filtered throughcelite and evaporated to give 0.95 g of material as a yellow solid(quant.), which was used as such for the next step.

MS: M+H=227.C.6-(3-Chloropyridin-2-yl)-5,6,7,8-tetrahydro-N-phenylpyrido[4,3-d]pyrimidin-4-amine

5,6,7,8-Tetrahydro-N-phenylpyrido[4,3-d]pyrimidin-4-amine (500 mg, 2.2mmol) was dissoled in a mixture of dioxane/N,N-dimethylacetamide (4:1)(2 mL). To the mixture was added 2,3-dichloropyridine (423 mg, 2.86mmol) and N,N-diisopropylethylamine (0.38 mL, 2.2 mmol). The mixture washeated at 150° C. in a microwave (Emrys Optimizer model, PersonalChemistry) for 16 h. The solvents were removed under vacuum and theresidue was dissolved in ethyl acetate and washed with sat. NaHCO₃ andbrine. The organic layer was dried over Na₂SO₄, filtered and evaporatedto give a brown residue. The residue was purified using a gradient ofethyl acetate:hexane (0-100%) to give the desired compound as anoff-white powder (190 mg).

¹H NMR (DMSO-d6): δ 8.58 (s, 1H). 8.40 (s, 1H) 8.28 (dd, 4.8 Hz, 1.7 Hz,1H); 8.28 (dd, 4.8 Hz, 1.7 Hz, 1H); 7.88 (dd, 7.8 Hz, 1.7 Hz, 1H);7.67-7.63 (m, 2H); 7.28-7.34 (m, 2H); 7.10-7.03 (m, 2H); 4.39 (s, 2H)3.62 (t, 5.8 Hz, 2H) 2.88 (t, 5.8 Hz, 2H).

Compound 36-(3-Chloropyridin-2-yl)-N-(4-fluorophenyl)-5,6,7,8-tetrahydropyrido4,3-d]pyrimidin-4-amine

A.6-Benzyl-N-(4-fluorophenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine

6-Benzyl-4-chloro-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidine(Intermediate 2, 0.25 g, 0.97 mmol) was dissolved in anhydrousacetonitrile (3 mL) and 4-fluorobenzenamine was added (0.10 mL, 1.06mmol). The mixture was heated at 200° C. for 600 s in a microwave (EmrysOptimizer model, Personal Chemistry). The solvents were removed undervacuum to give the desired product as a beige powder (0.313 g, 97%.).

MS: M+H=335.B. N-(4-Fluorophenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine

6-Benzyl-N-(4-fluorophenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine(0.64 g, 1.9 mmol) was dissolved in methanol (25mL) and palladiumhydroxide was added (0.5 g, 20% wt).The mixture was shaken on a ParrShaker under H₂ (g) atmosphere (60 PSI) for 1 day. The mixture wasfiltered through celite and evaporated to give 0.47 g of material whichwas used as such for the next step.

MS: M+H=245.C.6-(3-Chloropyridin-2-yl)-N-(4-fluorophenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine

N-(4-Fluorophenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine(0.47 g, 1.92 mmol) was dissolved in a mixture ofdioxane/N,N-dimethylacetamide (4:1) (3 mL). To the mixture was added2,3-dichloropyridine (420 mg, 2.86 mmol) and N,N-diisopropylethylamine(0.38 mL, 2.2 mmol). The mixture was heated at 150° C. in a PersonalChemistry microwave for 16 h. The solvents were removed under vacuum andthe residue was dissolved in ethyl acetate and washed with sat. NaHCO₃and brine. The organic layer was dried over Na₂SO₄, filtered andevaporated to give a brown residue. The residue was purified by silicagel chromatography using a gradient of ethyl acetate:hexane (0-100%) togive the desired compound as an off-white powder (200 mg, 30%).

¹H NMR (DMSO-d6): δ 8.62 (s, 1H); 8.38 (s, 1H); 8.28 (dd, 4.7 Hz, 1.4Hz, 1H) 7.89 (dd, 7.8 Hz, 1.4 Hz, 1H); 7.67-7.61(m, 2H); 7.19-7.12 (m,2H); 7.08 (dd, 7.8 Hz, 4.7 Hz, 1H); 4.38 (s, 2H); 3.61 (t, 5.4 Hz, 2H);2.88 (t, 5.4 Hz, 2H).

Compound 46-(3-Chloropyridin-2-yl)-N-(6-(trifluoromethyl)pyridin-3-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine

A.6-Benzyl-N-(6-(trifluoromethyl)pyridin-3-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine

6-Benzyl-4-chloro-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine (0.5 g, 1.93mmol) was dissolved in anhydrous dioxane (3 mL) and6-trifluoromethylpyridin-3-ylamine was added (469 mg, 2.9 mmol),followed by HI/H₂O (0.3 mL, 47%). The mixture was heated at 130° C. for600 s in a Personal Chemistry microwave. The solvents were removed undervacuum and the residue was dissolved in ethyl acetate and washed withsat. NaHCO₃ and brine. The organic layer was dried over Na₂SO₄, filteredand evaporated to give the product as an orange solid (700 mg, 95%crude). The crude product was used for the subsequent step.

MS: M+H=386.B.N-(6-(Trifluoromethyl)pyridin-3-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine

6-Benzyl-N-(6-(trifluoromethyl)pyridin-3-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine(1.7 g, 4.4 mmol) was dissolved in methanol (25 mL) and palladiumhydroxide was added (0.2 g, 20% wt). The mixture was shaken on a ParrShaker under H₂(g) atmosphere (60 PSI) for 1 day. The mixture wasfiltered through celite and evaporated to give 1.3 g (quant.) as anorange oil, which was used as such for the next step.

MS: M+H=296.C.6-(3-Chloropyridin-2-yl)-N-(6-(trifluoromethyl)pyridin-3-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine

N-(6-(Trifluoromethyl)pyridin-3-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine( 130 mg, 0.44 mmol) was dissolved in a mixture ofdioxane/N,N-dimethylacetamide (4:1) (2 mL). To the mixture was added2,3-dichloropyridine (98 mg, 0.66 mmol) and N,N-diisopropylethylamine(0.11 mL, 0.66 mmol). The mixture was heated at 150° C. in a PersonalChemistry microwave for 16 h. The solvents were removed under vacuum andthe residue was dissolved in ethyl acetate and washed with sat. NaHCO₃and brine. The organic layer was dried over Na₂SO₄, filtered andevaporated to give a brown residue. The residue was purified using agradient of ethyl acetate: hexane (0-100%) to give the desired compoundas an off-white powder (50 mg, 28%).

¹H NMR (DMSO-d6): δ 9.15 (s, 1H). 9.05 (d, 2.4 Hz, 1H); 8.54 (s, 1H);8.44 (dd, 8.7 Hz, 2.4 Hz, 1H); 8.29 (dd, 4.6 Hz, 1.6 Hz, 1H); 7.90 (dd,7.8 Hz, 1.6 Hz, 1H); 7.85 (d, 8.7 Hz, 1H); 7.09 (dd, 7.8 Hz, 4.6 Hz,1H); 4.45 (s, 2H); 3.63 (t, 5.6 Hz, 2H); 2.95 (t, 5.6 Hz, 2H).

Compound 5N-(6-(Trifluoromethyl)pyridin-3-yl)-5,6,7,8-tetrahydro-6-(3-(methylsulfonyl)pyridin-2-yl)pyrido[4,3-d]pyrimidin-4-amine

The title compound was prepared according to the procedure described forCompound 4 and reactingN-(6-(trifluoromethyl)pyridin-3-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine(140 mg, 0.47 mmol) with 2-chloro-3-(methylsulfonyl)pyridine(Ponticello, JOC, 44(17), 1979) (0.115 g, 0.06 mmol) in the presence ofN,N-diisopropylethylamine (0.17 mL, 0.98 mmol) to give the desiredCompound 5 as an off-white powder (55 mg, 26%).

¹H NMR (DMSO-d6): δ 9.07 (s, 1H). 9.04 (d, 2.3 Hz, 1H) 8.74 (dd, 4.7 Hz,1.9 Hz, 1H); 8.46 (dd, 8.7 Hz, 2.3 Hz, 1H); 8.56 (s, 1H); 8.37 (dd, 7.8Hz, 1.9 Hz, 1H); 7.85 (d, 8.7 Hz, 1H); 7.52 (dd, 7.8 Hz, 4.7 Hz, 1H);4.39 (s, 2H); 3.33 (s, 3H); 3.53 (t, 5.7 Hz, 2H); 2.99 (t, 5.7 Hz, 2H).

Compound 66-(3-Chloropyridin-2-yl)-5,6,7,8-tetrahydro-N-(4-(trifluoromethylsulfonyl)phenyl)pyrido[4,3-d]pyrimidin-4-amine

A.6-Benzyl-5,6,7,8-tetrahydro-N-(4-(trifluoromethylsulfonyl)phenyl)pyrido[4,3-d]pyrimidin-4-amine

The title compound was prepared substantially according to the proceduregiven for Compound 4A, using6-benzyl-4-chloro-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine (0.2 g, 0.77mmol), and 4-(trifluoromethylsulphonyl)aniline (0.27 g, 1.2 mmol) togive the desired N-benzyl intermediate as a brown solid (278 mg. 82%).

MS: M+H=449.B.5,6,7,8-Tetrahydro-N-(4-(trifluoromethylsulfonyl)phenyl)pyrido[4,3-d]pyrimidin-4-amine

6-Benzyl-5,6,7,8-tetrahydro-N-(4-(trifluoromethylsulfonyl)phenyl)pyrido[4,3-d]pyrimidin-4-amine (270 mg, 0.55 mmol) was dissolvedin anhydrous chloroform (10 mL) and 1-chloroethylchloroformate was added(0.18 mL, 1.65 mmol). After stirring for 30 min,N,N-diisopropylethylamine was added (0.24 mL, 1.65 mmol) and the mixturewas stirred for an additional 2 h. The chloroform was removed undervacuum and 30 ml of methanol was added and the mixture was heated for 30min. Upon reaction completion, the methanol was removed and the residuewas dissolved in ethyl acetate and washed with sat. NaHCO₃ and brine.The organic layer was dried over Na₂SO₄, filtered and evaporated to givethe product (163 mg, 83%).

M+H=359.C.6-(3-Chloropyridin-2-yl)-5,6,7,8-tetrahydro-N-(4-(trifluoromethylsulfonyl)phenyl)pyrido[4,3-d]pyrimidin-4-amine

The title compound was prepared according to the procedure given forCompound 4C using5,6,7,8-tetrahydro-N-(4-(trifluoromethylsulfonyl)phenyl)pyrido[4,3-d]pyrimidin-4-amine(160 mg, 0.45 mmol), 2,3-dichloropyridine (135 mg, 0.9 mmol) andN,N-diisopropylethylamine (0.16 mL, 0.9 mmol) to give the desiredcompound as an off-white powder (40 mg, 19%).

Compound 75,6,7,8-tetrahydro-6-(3-(methylsulfonyl)pyridin-2-yl)-N-(4-(trifluoromethylsulfonyl)phenyl)pyrido[4,3-d]pyrimidin-4-amine

The title compound was prepared according to the procedure given forCompound 4C. using 5,6,7,8-tetrahydro-N-(4-(trifluoromethylsulfonyl)phenyl)pyrido[4,3-d]pyrimidin-4-amine (308 mg, 0.86 mmol),2-chloro-3-(methylsulfonyl)pyridine (Ponticello, JOC, 44(17), 1979)(0.200 g, 1.04 mmol) and N,N-diisopropylethylamine (0.25 ml, 1.43 mmol)to give the desired compound as an off-white powder (75mg, 19%).

¹H NMR (DMSO-d6): δ 9.28 (s, 1H). 8.74 (dd, 4.8 Hz, 1.8 Hz, 1H); 8.64(s, 1H); 8.37 (dd, 7.8 Hz, 1.8 Hz, 1H); 8.20 (d, 9.0 Hz, 2H); 8.02 (d,9.0 Hz, 2H); 7.51 (dd, 7.8 Hz, 4.8 Hz, 1H); 4.41 (s, 2H); 3.53 (t, 5.6Hz, 2H); 3.31 (s, 3H); 3.0 (t, 5.6 Hz, 2H);

Compound 85,6,7,8-Tetrahydro-N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-6-m-tolylpyrido[4,3-d]pyrimidin-4-amine

A.6-Benzyl-5,6,7,8-tetrahydro-N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)pyrido[3,4-d]pyrimidin-4-amine

The title compound can be prepared using the general procedure set forthfor Compound 1, above, using 2,3-dihydrobenzo[b][1,4]dioxin-6-amine(0.32 mL, 2.63 mmol) and6-benzyl-4-chloro-5,6,7,8-tetrahydropyrido[3,4-d]pyrimidine (Compound1B) (0.621 g, 2.39 mmol) in acetonitile (3 mL).B.5,6,7,8-Tetrahydro-N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)pyrido[4,3-d]pyrimidin-4-amine

A mixture of6-benzyl-5,6,7,8-tetrahydro-N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)pyrido[3,4-d]pyrimidin-4-amine(0.742 g, 1.98 mmol), ammonium formate (1.25 g, 19.83 mmol) andpalladium, 10% wt. on activated carbon (75 mg) in methanol (10 mL) isheated to 60° C. for 2 h. The mixture is cooled to r.t. and filteredover celite. The filtrate is concentrated under reduced pressure to givea white solid which is dissolved in water. The mixture is extractedtwice with a 3:1 mixture of chloroform: isoproanol. The combined organicextracts are dried over sodium sulfate and concentrated to dryness togive the title compound.

C.5,6,7,8-Tetrahydro-N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-6-m-tolylpyrido[4,3-d]pyrimidin-4-amine

5,6,7,8-Tetrahydro-N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)pyrido[4,3-d]pyrimidin-4-amine(110 mg, 0.39 mmol) was dissolved in anhydrous THF (2 mL). To themixture was added m-tolylboronic acid (105 mg, 0.78 mmol), Cu(OAc)₂ (141mg, 0.78 mmol) and triethylamine (0.68 g, 0.095 mL) and 390 mg ofcrushed, activated 4A molecular seives. The mixture was agitated for 6 hand the solvent was removed under vacuum. The residue was purified usinga gradient of ethyl acetate:hexane (0-100%) to give the desired compoundas reddish powder (14 mg, 9.6%).

Compound 9N-(4-(Trifluoromethyl)phenyl)-5,6,7,8-tetrahydro-6-phenylpyrido[4,3-d]pyrimidin-4-amine

The(5,6,7,8-Tetrahydro-pyrido[4,3-d]pyrimidin-4-yl)-(4-trifluoromethylphenyl)amine(100 mg, 0.34 mmol) was dissolved in anhydrous THF (2 mL). To themixture was added phenylboronic acid (83 mg, 0.68 mmol), Cu(OAc)₂ (124mg, 0.68 mmol) and triethylamine (0.68 g, 0.095 mL). The mixture wasagitated for 6 h and the solvent was removed under the vacuum. Theresidue was purified using a gradient of ethyl acetate: hexane (0-100%)to give the desired compound as reddish powder (8.0 mg, 6.0%).

¹H NMR (DMSO-d6): δ 8.82 (s, 1H). 8.50 (s, 1H); 7.96 (d, 8.8 Hz, 2H);7.71 9d, 8.8 Hz, 2H); 7.32-7.26 (m, 2H); 7.20-7.15 (m, 2H); 6.85-6.80(m, 1H); 4.27 (s, 2H); 3.61 (t, 5.8 Hz, 2H); 2.90 (t, 5.8 Hz, 2H).

Compound 10N-(4-(Trifluoromethyl)phenyl)-5,6,7,8-tetrahydro-6-o-tolylpyrido[4,3-d]pyrimidin-4-amine

N-(4-(Trifluoromethyl)phenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine(100 mg, 0.34 mmol) was dissolved in anhydrous THF (2 mL). To themixture was added o-tolylboronic acid (92 mg, 0.68 mmol), Cu(OAc)₂ (124mg,0.68 mmol) and triethylamine (0.68 g, 0.095 mL). The mixture wasagitated for 6 h and the solvent was removed under a vacuum. The residuewas purified using a gradient of ethyl acetate:hexane (0-100%) to givethe desired compound as reddish powder (6.0 mg, 5%).

Compound 11N-(4-(Trifluoromethyl)phenyl)-5,6,7,8-tetrahydro-6-m-tolylpyrido[4,3-d]pyrimidin-4-amine

N-(4-(Trifluoromethyl)phenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine(100 mg, 0.34 mmol) was dissolved in anhydrous THF (2 mL). To themixture was added m-tolylboronic acid (92 mg ,0.68 mmol), Cu(OAc)₂ (124mg, 0.68 mmol) and triethylamine (0.68 g, 0.095 mL). The mixture wasagitated for 6 h and the solvent was removed under a vacuum. The residuewas purified using a gradient of ethyl acetate:hexane (0-100%) to givethe desired compound as reddish powder(6.2 mg, 5%).

¹H NMR (DMSO-d6): δ 8.81 (s, 1H). 8.50 (s, 1H); 7.97 (d, 8.8 Hz, 2H);7.71 (d, 8.8 Hz, 2H); 7.19-7.14(m, 1H); 7.01-6.94 (m, 2H); 6.65 (d, 7.6Hz, 1H); 4.25 (s, 2H); 3.58 (t, 5.6 Hz, 2H); 2.89 (t, 5.6 Hz, 2H); 2.30(s, 3H).

Compound 12N-(4-(Trifluoromethyl)phenyl)-5,6,7,8-tetrahydro-6-p-tolylpyrido[4,3-d]pyrimidin-4-amine

N-(4-(Trifluoromethyl)phenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine(100 mg, 0.34 mmol) was dissolved in anhydrous THF (2 mL). To themixture was added p-tolylboronic acid (92 mg, 0.68 mmol), Cu(OAc)₂ (124mg,0.68 mmol) and triethylamine (0.68 g, 0.095 mL). The mixture wasagitated for 6 h and the solvent was removed under a vacuum. The residuewas purified using a gradient of ethyl acetate:hexane (0-100%) to givethe desired compound as reddish powder (12.8 mg, 10%).

¹H NMR (DMSO-d6): δ 8.80 (s, 1H). 8.49 (s, 1H); 7.96 (d, 8.7 Hz, 2H);7.7 (d, 8.7 Hz, 2H); 7.10 (d, 9.1 Hz, 2H); 7.07 (d, 9.1 Hz, 2H); 4.21(s, 2H); 3.54 (t, 5.7 Hz, 2H); 2.88 (t, 5.7 Hz, 2H); 2.23 (s, 3H).

Compound 136-[6-(3-Chloro-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-ylamino]-3,3-dimethyl-1,3-dihydro-indol-2-one

A. 6-amino-3,3-dimethylindolin-2-one

A mixture of 3,3-dimethyl-6-nitroindolin-2-one (1.2 g, 5.8 mmol)(Mertens et al, J. Med. Chem. 30:1279, 1987), 10% Pd—C (100 mg), andMeOH (100 mL) was stirred under hydrogen atmosphere (1 atm) for 10 h.The catalyst was filtered out and the filtrate was concentrated. Theresidue was purified by column to give an off-white solid (700 mg).

MS: M+H=177.

¹H NMR (d6-DMSO): 10.01 (s, 1H), 6.84 (d, 1H, J=8.0 Hz), 6.13-6.10 (m,2H), 5.01 (s, 2H), 1.15 (s, 6H).

B.6-(6-(3-chloropyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-ylamino)-3,3-dimethylindolin-2-one

A mixture of 6-amino-3,3-dimethylindolin-2-one (156 mg),4-chloro-6-(3-chloropyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine(100 mg), and CH₃CN (5 mL) was run in a Microwave Reactor at 180° C. for1 h. After cooling, the mixture was treated with sat. aq. Na₂CO₃ andextracted with EtOAc (30 mL×3). The combined organic layers were washedwith brine, dried (Na₂SO₄) and concentrated. The residue was purified bycolumn to give an off-white solid (120 mg, 80%).

¹H NMR (d6-DMSO): 10.32 (s, 1H), 8.54 (s, 1H), 8.40 (s, 1H), 8.28 (dd,1H, J=5.2, 1.6 Hz), 7.89 (dd, 1H, J=8.0, 1.6 Hz), 7.30 (s, 1H), 7.19 (s,2H), 7.08 (dd, 1H, J=8.0, 4.8 Hz), 4.38 (s, 2H), 3.61 (t, 2H, J=6.0 Hz),2.88 (t, 2H, J=5.6 Hz), 1.24 (s, 6H).

Compound 141-{6-[6-(3-Chloro-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-ylamino]-3,3-dimethyl-2,3-dihydro-indol-1-yl}-ethanone

A. 3,3-dimethyl-6-nitroindoline

To a stirred solution of 3,3-dimethyl-6-nitroindolin-2-one (0.6 g, 3mmol) (Mertens et al., J. Med. Chem. 30:1279,1987) in THF (40 mL) at 0°C. under N₂ was added 2.0 M solution of BH₃·Me₂S complex in THF (10 mL,20 mmol). The mixture was stirred at rt for 10 h, and then quenched byaddition of water (10 mL) and concentrated HCl (20 mL). The mixture wasfurther stirred at rt for 5 h, and then basified with sat. aq. Na₂CO₃and extracted with EtOAc (50 mL×3). The combined organic layers werewashed with brine, dried (Na₂SO₄) and concentrated to give an orangesyrup.

MS: M+H=193.

B. 1-(3,3-dimethyl-6-nitroindolin-1-yl)ethanone

To a stirred solution of 3,3-dimethyl-6-nitroindoline (450 mg) in CH₂Cl₂(15 mL) and Et₃N (0.6 mL) at −10° C. was added acetyl chloride (180 μL,2.5 mmol). The mixture was stirred at rt overnight and quenched byaddition of sat. aq. NaHCO₃, and extracted with EtOAc (30 mL×3). Thecombined organic layers were washed with brine, dried (MgSO₄) andconcentrated. The residue was purified by column to give a light yellowsolid (390 mg, 71% for two steps).

MS: M+H=235.

C. 1-(6-amino-3,3-dimethylindolin-1-yl)ethanone

A mixture of 1-(3,3-dimethyl-6-nitroindolin-1-yl)ethanone (300 mg), 10%Pd—C (50 mg), and EtOH (50 mL) was stirred under hydrogen atmosphere (1atm) for 3 h. The catalyst was filtered out and the filtrate wasconcentrated to give a light yellow solid (260 mg).

MS: M+H=205.

D.1-{6-[6-(3-chloro-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-ylamino]-3,3-dimethyl-2,3-dihydro-indol-1-yl}-ethanone

A mixture of 1-(6-amino-3,3-dimethylindolin-1-yl)ethanone (80 mg),4-chloro-6-(3-chloropyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine(80 mg), and CH₃CN (5 mL) was run in a Microwave Reactor at 180° C. for1 h. After cooling, the mixture was treated with sat. aq. Na₂CO₃ andextracted with EtOAc (30 mL×3). The combined organic layers were washedwith brine, dried (Na₂SO₄) and concentrated. The residue was purified bycolumn to give a light yellow solid (75 mg).

¹H NMR (d6-DMSO): 8.61 (s, 1H), 8.34 (s, 1H), 8.28 (dd, 1H, J=4.8, 1.6Hz), 8.19 (d, 1H, J=1.6 Hz), 7.88 (dd, 1H, J=8.0, 1.6 Hz), 7.35 (dd, 1H,J=8.0, 2.0 Hz), 7.15 (d, 1H, J=8.0 Hz), 7.07 (dd, 1H, J=8.0, 4.8 Hz),4.38 (s, 2H), 3.86 (s, 2H), 3.61 (t, 2H, J=5.6 Hz), 2.87 (t, 2H, J=5.6Hz), 2.16 (s, 3H), 1.30 (s, 6H).

Compound 15[6-(3-Chloro-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-(3,3-dimethyl-2,3-dihydro-1H-indol-6-yl)-amineHCl salt

A mixture of1-{6-[6-(3-chloro-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-ylamino]-3,3-dimethyl-2,3-dihydro-indol-1-yl}-ethanone(30 mg), EtOH (5 mL), and 5N aqueous HCl (1 mL) was stirred at 55° C.for 10 h. The mixture was concentrated in vacue to give the HCl salt asa light yellow solid (35 mg).

¹H NMR (d6-DMSO): 10.38 (s, 1H), 8.81 (s, 1H), 8.30 (dd, 1H, J=4.8, 1.6Hz), 7.93 (dd, 1H, J=8.0, 1.6 Hz), 7.55-7.42 (m, 3H), 7.13 (dd, 1H,J=8.0, 4.8 Hz), 4.46 (s, 2H), 3.66 (t, 2H, J=5.6 Hz), 3.48 (s, 2H), 3.06(t, 2H, J=5.6 Hz), 1.37 (s, 6H).

Compound 16[6-(3-Chloro-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-(3,3-dimethyl-2,3-dihydro-1-methyl-indol-6-yl)-amine

To a stirred mixture of[6-(3-chloro-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-(3,3-dimethyl-2,3-dihydro-1H-indol-6-yl)-amineHCl salt (10 mg), DMF (5 mL), and K₂CO₃ (50 mg) was added Mel (50 μL).The reaction mixture was stirred at rt for 5 h, and then diluted withEtOAc (50 mL). The organic phase was washed with brine, dried (Na₂SO₄)and concentrated. The residue was purified by column to give anoff-white solid (7 mg).

¹H NMR (d6-DMSO): 8.35 (s, 2H), 8.28 (dd, 1H, J=4.8, 1.6 Hz), 7.88 (dd,1H, J=8.0, 1.6 Hz), 7.07 (dd, 1H, J=8.0, 4.4 Hz), 6.91 (s, 2H), 6.73 (s,1H), 4.35 (s, 2H), 3.61 (t, 2H, J=5.6 Hz), 3.03 (s, 2H), 2.86 (t, 2H,J=5.6 Hz), 2.67 (s, 3H), 1.23 (s, 6H).

Compound 17(6-tert-Butyl-pyridin-3-yl)-[6-(3-chloro-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine

A.(6-Benzyl-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl)-(6-tert-butyl-pyridin-3-yl)-amine

The title compound was prepared substantially according to the proceduregiven for Compound 1A, using6-benzyl-4-chloro-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine(Intermediate 2), and 6-tert-butyl-pyridin-3-ylamine to give the desiredN-benzyl intermediate as a brown solid.B.(5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl)-(6-tert-butyl-pyridin-3-yl)-amine

The title compound was prepared substantially according to the proceduregiven for Compound 1B by deprotection of6-benzyl-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl)-(6-tert-butyl-pyridin-3-yl)-amine.C.(6-tert-Butyl-pyridin-3-yl)-[6-(3-chloro-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine

The title compound was prepared according to the procedure given forCompound 1C by reacting(5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl)-(6-tert-butyl-pyridin-3-yl)-aminewith 2,3-dichloropyridine to give the desired compound as an off-whitepowder.

Compound 183,3-Dimethyl-1-{[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-ylamino]-methyl}-cyclohexanol

4-chloro-5,6,7,8-tetrahydro-6-(5-methylpyridin-2-yl)pyrido[4,3-d]pyrimidine(0.030 g, 0.00012 mol) and 1-aminomethyl-3,3-dimethyl-cyclohexanol(0.022 g, 0.00014 mol) in acetonitrile (3 mL, 0.06 mol) was heated viamicrowave in a sealed tube at at 180° C. for a total of 2 hours and fiveminutes. The reaction mixture was cooled to room temperature and pouredinto saturated sodium bicarbonate. The mixture was extracted with equalamounts of ethyl acetate and the organic layer was dried over magnesiumsulfate. The residue was purified by flash chromatography over silicagel methanol/dichloromethane (0-10%) to yield the title compound.

Compounds 24-33 and 35-129 General Synthesis Synthesis of aminosubstituted5,6,7,8-tetrahydro-6-(5-methylpyridin-2-yl)pyrido[4,3-d]pyrimidine

A. 5,6,7,8-Tetrahydro-3H-pyrido[4,3-d]pyrimidin-4-one

A mixture of 6-benzyl-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(3H)-one(Intermediate 2, 18.0 g, 0.0738 mol), triethylamine (48 mL, 0.34 mol)Palladium hydroxide (10 g, 0.07 mol) in methanol (242 mL, 5.91 mol) washeated to 60° C. Formic acid (7.6 mL, 0.20 mol) was added dropwise tothe mixture over a 15 minute period. The mixture was heated at at 65° C.for three hours, allowed to cool, and filtered over Celite. The filtratewas concentrated under reduced vacuum to yield the title compound as ayellow solid which was used directly in the next reaction. (9.62 g,77.6%).

MS:M+H=152.2.B.5,6,7,8-Tetrahydro-6-(5-methylpyridin-2-yl)pyrido[4,3-d]pyrimidin-4(3H)-one

Into a 20 ml microwave tube was combined5,6,7,8-Tetrahydro-3H-pyrido[4,3-d]pyrimidin-4-one (0.280 g, 0.00183mol), 2-chloro-5-methylpyridine (0.47 g, 0.0037 mol), 1,4-dioxane (2.5mL, 0.032 mol) N,N-diisopropylethylamine (0.64 mL, 0.0037 mol) andN,N-dimethylacetamide (0.5 mL, 0.005 mol). The mixture was heated viamicrowave at 150° C. for 4 hours. The mixture was reduced in vacuo andtaken up in chloroform:IPA (3:1) (50 ml). The organic was washed withsodium bicarbonate and brine (1×50 ml), dried over sodium sulfate, andreduced in vacuo. The mixture was purified by flash chromatography onsilica gel using a methylene chloride: methanol (0-10%) gradient. Thecombined pure fractions were reduced in vacuo to yield a bright yellowsolid (0.215 g, 47.9%).

MS:M+H=243.28.

¹H NMR (DMSO-d6): δ 12.50 (brs, 1H), 8,05 (s, 1H) 7.98 (d, 1H), 7.41(dd, 1H), 6.84 (d, 1H), 4.24, (s, 2H), 3.77 (t, 2H), 2.67 (t, 2H), 2.15(s 3H).C.4-Chloro-5,6,7,8-tetrahydro-6-(5-methylpyridin-2-yl)pyrido[4,3-d]pyrimidine

Into a 250 ml round bottom flask was combined5,6,7,8-tetrahydro-6-(5-methylpyridin-2-yl)pyrido[4,3-d]pyrimidin-4(3H)-one(0.250 g, 0.00103 mol), phosphoryl chloride (0.8 mL, 0.008 mol), and1,2-dichloroethane (10 mL, 0.1 mol). N,N-Dimethylaniline (0.01 g, 0.0001mol) was added dropwise and the mixture was heated at reflux for 2hours. The mixture was reduced in vacuo to yield a dark brown oil. Theoil was taken up in methylene chloride (50 ml) and poured over ice. Themixture was carefully neutralized using sat sodium bicarbonate. Thelayers were separated and the organic was dried over sodium sulfate andreduced in vacuo. The mixture was purified by falsh chromatography onsilica gel using methylene chloride:methanol (0-10%). The combined purefractions were reduced in vacuo to yield a bright yellow solid. (0.141g, 52.4%).

MS:M+H=260.8.

¹H NMR (DMSO-d6): δ 8.83 (s, 1H), 8.00 (d, 1H), 7.50 (d, 1H), 6.99 (d,1H), 4.67 (s, 2H), 3.89 (t, 2H), 2.98 (t, 2H), 2.16 (s, 3H).D. 4-Substitutedamino-5,6,7,8-tetrahydro-6-(5-methylpyridin-2-yl)pyrido[4,3-d]pyrimidine

Into a 5 ml microwave reaction tube was combined4-chloro-5,6,7,8-tetrahydro-6-(5-methylpyridin-2-yl)pyrido[4,3-d]pyrimidine(0.015 mg, 0.05 mmol), benzylamine (1 eq), acetontirile (800 ul) andDIPEA (2.0 eq). The mixture was heated at 150 degrees for 15 minutes.The volatiles were removed under reduced pressure and the mixture waspurified by supercritical fluid chromatography to yield the desiredproduct.

The following compounds (24-33 and 35-129) can be prepared substantiallyaccording to the procedure given above using4-chloro-6-(5-methylpyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidineand an appropriate amine to give the corresponding aminotetrahydropyrido[4,3-d]pymidine derivatives, as shown in Table 1. TABLE1 ID Amine Structure 24 2-Methyl-benzylamine

25 4-Chloro-benzylamine

26 C-Cyclohexyl- methylamine

27 2-Methoxy- benzylamine

28 3-Methoxy- benzylamine

29 C-(1-p-Tolyl- cyclohexyl)- methylamine

30 2-Chloro-benzylamine

31 2-Ethoxy-benzylamine

32 2-(2-Chloro-phenyl)- ethylamine

33 C-Adamantan-1-yl- methylamine

35 2-(4-Methoxy-phenyl)- ethylamine

36 Benzyl-methyl-amine

37 C-Benzo[1,3]dioxol-5- yl-methylamine

38 3-Trifluoromethyl- benzylamine

39 2-Trifluoromethyl- benzylamine

40 4-Trifluoromethoxy- benzylamine

41 3-Trifluoromethoxy- benzylamine

42 2-Trifluoromethoxy- benzylamine

43 Indan-1-ylamine

44 4-tert-Butyl- benzylamine

45 Phenethylamine

46 2-(3-Methoxy-phenyl)- ethylamine

47 2-(3,4-Dimethoxy- phenyl)-ethylamine

48 2-(4-Chloro-phenyl)- ethylamine

49 2-p-Tolyl-ethylamine

50 4-Trifluoromethyl- benzylamine

51 2-(3,5-Dimethoxy- phenyl)-ethylamine

52 2-Difluoromethoxy- benzylamine

53 4-Methoxy- benzylamine

54 2-(3,4-Dichloro- phenyl)-ethylamine

55 3-Chloro-benzylamine

56 4-Methyl-benzylamine

57 3-Fluoro-benzylamine

58 4-Isopropyl- benzylamine

59 (3,4-Dimethoxy- benzyl)-methyl-amine

60 2-(4-Fluoro-phenyl)- 1,1-dimethyl- ethylamine

61 2-(3-Trifluoromethyl- phenyl)-ethylamine

62 (4-Chloro-benzyl)- methyl-amine

63 (2-Methoxy-benzyl)- methyl-amine

64 (3-Methoxy-benzyl)- methyl-amine

65 (4-Ethyl-benzyl)- methyl-amine

66 (3-Chloro-benzyl)- methyl-amine

67 (4-Fluoro-benzyl)- methyl-amine

68 (4-Methoxy-benzyl)- methyl-amine

69 Methyl-(4- trifluoromethyl-benzyl)- amine

70 Methyl-(4-methyl- benzyl)-amine

71 2,5-Difluoro- benzylamine

72 2,6-Difluoro- benzylamine

73 3,4-Difluoro- benzylamine

74 2-Fluoro-5- trifluoromethyl- benzylamine

75 3-Fluoro-5- trifluoromethyl- benzylamine

76 4-Fluoro-3- trifluoromethyl- benzylamine

77 2,3-Difluoro- benzylamine

78 2,4-Dichloro- benzylamine

79 2,4-Dimethyl- benzylamine

80 2,3-Dimethyl- benzylamine

81 1-Methyl-1-phenyl- ethylamine

82 4-Difluoromethoxy- benzylamine

83 4-Chloro-2-fluoro- benzylamine

84 3,4-Dimethoxy- benzylamine

85 3,4-Dichloro- benzylamine

86 1-(4-Fluoro-phenyl)- ethylamine

87 3,5-Dimethoxy- benzylamine

88 2,4-Dimethoxy- benzylamine

89 2-Chloro-5- trifluoromethyl- benzylamine

90 C-Pyridin-3-yl- methylamine

91 C-Pyridin-4-yl- methylamine

92 3-Methyl-benzylamine

93 4-Fluoro-benzylamine

94 3,5-Dimethyl- benzylamine

95 2,5-Dimethyl- benzylamine

96 3,4-Dimethyl- benzylamine

97 4-Ethyl-benzylamine

98 4-Fluoro-3-methyl- benzylamine

99 1-(3-Fluoro-phenyl- ethylamine

100 2,4-Difluoro- benzylamine

101 3,5-Difluoro- benzylamine

102 4-Chloro-2-methyl- benzylamine

103 5-Chloro-2-methyl- benzylamine

104 3-Chloro-2-methyl- benzylamine

105 1-(4-Chloro-phenyl)- ethylamine

106 2,6-Difluoro-3-methyl- benzylamine

107 C-Quinolin-6-yl- methylamine

108 4-Chloro-3-fluoro- benzylamine

109 2-Chloro-4-fluoro- benzylamine

110 3-Chloro-2-fluoro- benzylamine

111 5-Chloro-2-fluoro- benzylamine

112 3-Chloro-4-fluoro- benzylamine

113 2,6-Dimethoxy- benzylamine

114 2,3-Dimethoxy- benzylamine

115 3,5-Dichloro- benzylamine

116 2,3-Dichloro- benzylamine

117 1-(3-Trifluoromethyl- phenyl)-ethylamine

118 4-Fluoro-2- trifluoromethyl- benzylamine

119 5-Fluoro-2- trifluoromethyl- benzylamine

120 2-Fluoro-3- trifluoromethyl- benzylamine

121 2-Fluoro-4- trifluoromethyl- benzylamine

122 3-Fluoro-4- trifluoromethyl- benzylamine

123 1-(4-Methanesulfonyl- phenyl)-ethylamine

124 3-Phenoxy-benzylamine

125 3,5-Bis-trifluoromethyl- benzylamine

126 5-Fluoro-2-methyl- benzylamine

127 4-Chloro-3- trifluoromethyl- benzylamine

128 [(S)-1-(4-Chloro- phenyl)-ethyl]amine

129 [(R)-1-(4-Chloro- phenyl)-ethyl]amine

Compounds 19, 20 and 22

The following compounds (19, 20 and 22) can be prepared substantiallyaccording to the procedure given above using4-chloro-6-(5-trifluoromethylpyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidineand an appropriate amine to give the corresponding aminotetrahydropyrido[4,3-d]pyrimidine derivatives, as shown in Table 2.TABLE 2 ID Amine Structure 19 Benzylamine

20 2-(2-chloro-phenyl) ethylamine

22 C-cyclohexyl- methylamine

Compounds 21 and 23

The following compounds (21 and 23) can be prepared substantiallyaccording to the procedure given above using4-chloro-6-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine andan appropriate amine to give the corresponding aminotetrahydropyrido[4,3-d]pyrimidine derivatives, as shown in Table 3.TABLE 3 ID Amine Structure 21 C-cyclo- hexylmethyl amine

23 2-(2-chloro- phenyl) ethylamine

Compound 346-(3-Chloropyridin-2-yl)-N-(4-(trifluoromethyl)phenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine

A.6-Benzyl-N-(4-(trifluoromethyl)phenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine

6-Benzyl-4-chloro-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidine (0.6 g, 2.3mmol) was dissolved in anhydrous dioxane (2 mL) and4-(trifluoromethyl)aniline was added (0.43 mL, 3.45 mmol), followed byHI/H₂O (0.2 ml, 47%). The mixture was heated at 130° C. in a sealed tubefor 10 min in a microwave (Smith creator model, Personal Chemistry). Thesolvents were removed under vacuum and the residue was dissolved inethyl acetate and washed with sat. NaHCO₃ and brine. The organic layerwas dried over Na₂SO₄, filtered and evaporated to give the desiredcompound as a yellow solid (800 mg, 91%) which was used as such for thenext step.

M+H=385.B.N-(4-(Trifluoromethyl)phenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine

6-Benzyl-N-(4-(trifluoromethyl)phenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine(1.5 g, 3.9 mmol) was dissolved in methanol (25 mL) and palladiumhydroxide was added (1.5 g, 20% wt). The mixture was shaken on a ParrShaker under H₂(g) atmosphere (60 PSI) for 3 days. The mixture wasfiltered through celite and evaporated to give 1.0 g of material as ayellow solid (87%), which was used as such for the next step.

MS: M+H=295.

¹H NMR (DMSO-d6): 8.61 (s, 0.8H)., 8.46 (s, 1H), 7.94 (d, 8.6 Hz, 2H),7.66 (d, 8.6 Hz, 2H), 3.84 (s, 2H), 3.05 (t, 5.6 Hz, 2H), 2.68 (t, 5.6Hz, 2H).C.6-(3-Chloropyridin-2-yl)-N-(4-(trifluoromethyl)phenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine

N-(4-(Trifluoromethyl)phenyl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-amine(700 mg, 3.4mmol) was dissolved in a mixture ofdioxane/N,N-dimethylacetamide (4:1) (2 mL). To the mixture was added2,3-dichloropyridine (1.5 g, 10.2 mmol) and N,N-diisopropylethylamine(0.87 mL, 5.1 mmol). The mixture was heated in a sealed tube at 150° C.in a microwave (Emrys Optimizer model, Personal Chemistry) for 16 h. Thesolvents were removed under vacuum and the residue was dissolved inethyl acetate and washed with sat. NaHCO₃ and brine. The organic layerwas dried over Na₂SO₄, filtered and evaporated to give a brown residue.The residue was purified using a gradient of ethyl acetate:hexane(0-100%) to give the desired compound as an off-white powder (340 mg,26%).

¹H NMR (DMSO-d6 8.91 (brs, 1H). 8.50 (s, 1H), 8.28 (dd, 4.7 Hz, 1. 6Hz,1H), 7.94 (d, 8.4 Hz, 2H), 7.89 (dd, 7.7 Hz, 1.6 Hz, 1H), 7.67 (d, 8.4Hz, 2H), 7.08 (dd, 7.6 Hz, 4.7 Hz, 1H), 4.44 (s, 2H), 3.63 (t, 5.6Hz,2H), 2.92 (t, 5.6 Hz, 2H).

Assays

Compounds provided herein can be evaluated using biochemical assays, forexample, binding assays to purinergic P2X2 and P2X3 receptors, can beevaluated using cell-based assays, or can be evaluated in animal painmodels. Examples of assays are described below.

The purinergic receptors P2X2 and P2X3 are expressed in a variety ofneuronal and non-neuronal tissues including various sensory andsympathetic ganglia, such as the dorsal root (DRG), nodose (ND),trigeminal (TG), and superior cervical ganglia (SCG) and also in smoothmuscle cells (Burnstock, Trends Pharmacol. Sci. 27:166-76, 2006). Inseveral regions, P2X2 and P2X3 receptors are coexpressed and functionalstudies have demonstrated the presence of heteromeric P2X2/3 receptorswhose properties differ from those of either homomeric receptor. Inaddition, chimeric P2X2/3 receptors, containing the N-terminalcytoplasmic domain of P2X2 fused to the first transmembrane domain ofP2X3 have been described; these chimeric channels retain thepharmacological profile of homomeric P2X3 receptor, while gaining thenon-desensitizing phenotype of the homomeric P2X2 receptor (Neelands etal., Br. J. Pharmacol. 140:202-10, 2003). The non-desensitizing behaviorof the chimeric receptor is especially useful for screening.

Members of the P2X family are ligand-gated non-selective cation channelswhose activity can be characterized by using electrophysiologicalmethods, or by measuring calcium ion influx using calcium-sensitivefluorescent dyes. Applications of agonists such as ATP, or an ATP analogsuch as α,β-Methyleneadenosine 5′-triphosphate (αβMeATP, Sigma-Aldrich),causes channel opening, resulting in current flow and calcium influx(Bianchi et al., Eur. J. Pharmacol. 376:127-38, 1999).

The compounds of the invention can be tested for antagonist activity atP2X3 and P2X2/3 receptors by measuring their ability to affect receptoropening by ATP, αβMeATP, or other agonists. Functional tests of receptoractivity include but are not limited to: (i) calcium ion influx measuredby fluorescence of a calcium sensitive dye and; (ii) ion flux resultingfrom channel opening measured by electrophysiological methods. Thesemethods can be used to evaluate channel function when the relevantreceptor is heterologously expressed in a mammalian or amphibian cells.These methods can also be used to evaluate compounds of the invention inrodent primary neurons and other mammalian primary cells and cell linesthat normally express the receptor of interest.

Compounds can further be evaluated for their ability to bind P2X3 andP2X2/3 receptors using biochemical approaches. Compounds can also beevaluated for their ability to modify sensory and autonomic nervoussystem signaling where the receptors are known to have a role (e.g.,urinary bladder afferent signaling, sensory nerve pain sensation).Finally, compounds of the invention can be tested in vivo in animal painmodels known to one skilled in the art, such as, for example, models ofneuropathic, inflammatory, or visceral pain, or models of urinaryincontinence.

The following biological examples are offered to illustrate the presentinvention and is not to be construed in any way as limiting in scopethereof.

Calcium Uptake Assay

Clones and Cell Lines:

Human P2X3 (Accession no. NM_(—)002559), P2X2 (Accession no.NM_(—)170682) and Rat P2X3 (Accession no. NM_(—)031075) and P2X2(Accession no. NM_(—)053656) are cloned into a mammalian expressionvector (e.g., pcDNA5/TO or pcDNA3 Invitrogen). For coexpression of P2X2and P2X3, the coding regions of both receptors were cloned into abicistronic vector using methods similar to those described by Kawashimaet al., Receptors Channels 5:53-60, 1998. The P2X2/3 chimera clone wascreated as described by Neelands et al, and then cloned into anexpression vector as above. Receptors are expressed in cells (e.g.,HEK293 or 1321N1) via transient transfection using standard lipidmediated transfection, or by creation of stable transfectants for eachreceptor. Cell lines are maintained in DMEM+5% Glutamax, the appropriatelevel of selective antibiotic, and 10% heat inactivated FBS.

P2X Antagonist Assay:

The agonist EC₅₀ is determined at the start of the assay and compoundIC₅₀ experiments are run using a set agonist concentration (EC₅₀₋₉₀depending on cell line) as stimulus. The agonists used are αβMeATP, ATP,or other ATP analogs. Compounds may be tested at concentrations rangingfrom 1 pM to 10 μM. Functional activity of compounds at the P2X receptoris determined by measuring their ability to inhibit agonist-inducedcalcium influx. Compounds may be tested for antagonist activity againstthe P2X2/3 chimera, the P2X3 homomer, or the P2X2/3 heteromer. To testfor antagonist activity, cells expressing the appropriate receptor areseeded onto 96 or 384 well plates 18-24 hours prior to assay. On the dayof the assay, cells are loaded with calcium-sensitive fluorescent dye(e.g., Fluo-4 no wash reagent-Invitrogen cat# F36206, or the BD™ PBXCalcium Assay Kit-BD cat# 640175) in Hank's Buffered Salt Solution(HBSS) with up to 10 mM supplemental CaCl₂. Plates are incubated at 37°C. and then equilibrated at room temperature. Antagonism ofagonist-induced calcium influx is measured using a fluorescent imagingplate reader. The assay comprises two stages: a pre-treatment phasefollowed by a treatment phase. Compounds may be tested as follows: Forthe pre-treatment phase, 50 μL of 3× concentration of test compound inHBSS is added to cells containing 100 μL of dye loading media to achievea final concentration of 1×. For the treatment phase, at a set intervalafter pre-treatment, 50 μL of 1× test compound plus 4× agonist solutionis added to cells. Fluorescence is measured at 0.1-3 secondintervals-with an excitation wavelength of 494 nM and an emissionwavelength of 515 nM. Responses are measured as peak fluorescence aftercompound-agonist addition minus baseline fluorescence prior totreatment. Percent inhibition is calculated as follows:${{Percentage}\quad{inhibition}}\quad = {1 - {\frac{\left( {{{Compound}{\quad\quad}{Response}} - {{Control}\quad{Response}}} \right)}{\left( {{{Agonist}\quad{Response}} - {{Control}\quad{Response}}} \right)} \times 100.}}$

Electrophysiological Experiments

Whole Cell Patch Clamp:

Whole cell recordings are made using the Multiclamp700A patch-clampamplifier and Clampex acquisition program (Molecular DevicesCorporation). Whole-cell recordings are obtained from stably ortransiently transfected 1321N1 or HEK cells. Solutions are eitherapplied for periods of 1 to 3s by a gravity flow, 8-valve deliverysystem, or for periods of milliseconds using the quick-change Dynaflowperfusion system (Cellectricon Inc.). The internal pipette solution mayinclude 140 mM Cesium-Chloride, 10 mM EGTA, and 5 mM Hepes at pH 7.2;normal external solution is 140 mM NaCl, 5 mM KCl, 1 mM CaCl₂, 2 mMMgCl₂, 25 mM Hepes, and 10 mM glucose. Concentration-response curves areobtained by recording currents in response to brief applications ofagonist at 1-3 min intervals where regular external solution is perfusedduring the intervals. To obtain inhibition curves, antagonists arepre-applied to the cells for a defined time period before a shortapplication of the agonist+antagonist. The periods of antagonistpre-application and agonist+antagonist applications are constant for theentire test concentration series. Agonist evoked currents are measuredin cells that are voltage clamped at −60 or −80 millivolts.

Oocyte Preparation:

Surgically removed Xenopus ovaries are obtained from NASCO. The oocytesare isolated by enzymatic dissociation using collagenase (Worthington, 2mg/ml). Oocytes are then individually injected with P2X3, P2X2, or acombination of P2X2 and P2X3 RNA. Each oocyte receives ˜64 nl of RNAsolution in water at a concentration of ˜0.01 μg/μl. Injected oocytesare stored in standard oocyte incubation solution, ND96, containing (inmM) 96 NaCl, 2 KCl, 1 MgCl₂, 1-5 CaCl₂ and 50 μg/ml Gentamicin at 16° C.Agonist-induced -current caused by P2X channel opening is observed inoocytes 1-5 days after injection.

Two-Electrode Voltage Clamp Recording:

Eight oocytes are placed in the recording chambers. Each oocyte isimpaled by 2 glass electrodes having resistances of 0.5 to 1 MOhm whenfilled with a 3 M KCl solution. Electrode advancement and oocyteimpalement are under software control (OPUSXPRESS 1.1, Molecular devicesCorporation). The solutions are prepared in 96 well plates androbotically pipetted into the oocyte recording chambers by an 8 channelpipettor. Test solution delivery to the oocytes during the experiment isalso under software control. A set of plates with wells containingagonist are used initially to verify P2X expression. A set of 96 wellplates containing the test solutions is prepared. Inhibition byantagonists is determined by calculating % current remaining whenoocytes are stimulated with agonist in the presence of test compoundcompared to the peak current in the presence of agonist alone. Thesequence of solution application to the oocyte is as follows: a specificconcentration (e.g., EC₅₀, EC₈₀, or EC₉₀) of the agonist is added firstto elicit the maximal response. After the pulse, oocytes are washed forseveral minutes with ND96. The test compound is then added at aparticular concentration, followed by the compound at the sameconcentration along with the agonist. In one instance, the testedconcentrations for the compounds may range from 0.3 to 10,000 nM.

Manual Two-Electrode Voltage Clamp:

Individual oocytes are impaled manually with 2 electrodes and agonistevoked current are measured using an Oocyte clamp amplifier (WarnerInstrument Corp.) and Clampex (Molecular Devices Corporation)acquisition software. Solutions are delivered using gravity flow andapplied as above. The agonist induced current is measured in the absenceand presence of antagonist. Antagonists are tested in a concentrationseries to obtain an inhibition curve.

Quantitative measurement of P2X current block is done by calculating thearea under the curve described by the inward current. The resultingnumbers for agonist-induced currents in the presence of increasingcompound concentration are normalized to the maximum current obtained.These points are then plotted on a logarithmic scale and fitted by aHill function. The IC₅₀ is calculated from the resulting Hill fit.

Selectivity Screens:

Compounds that inhibit P2X3 and/or P2X2/3H activation will be tested foractivity against other P2X receptors to determine their selectivity forspecific P2X family members. The list of receptors to be assayedincludes, but is not restricted to P2X1, P2X2, P2X4, P2X5, P2X6, andP2X7. The types of assay used for selectivity determination mayinclude: 1) Agonist-induced Calcium influx in cells heterologouslyexpressing the relevant receptor, 2) Electrophysiological determinationof receptor inhibition in either mammalian cells or Xenopus oocytesheterologously expressing the receptor of interest. Methods and dataanalysis will be similar to those described above for P2X3 and P2X2/3H.

Radioligand Binding:

Radioligand experiments are done to determine the affinity of testcompounds for P2X3 homomeric and P2X2/3 heteromeric receptors. Thesestudies also provide valuable insights into the mechanism of action ofantagonism. The general methodologies used for radioligand bindingexperiments for P2X3 and P2X2/3 receptors are described by Jarvis etal., J. Pharmacol. Exp. Ther. 10:407-16, 2004.

Briefly, cell membranes are prepared from cells transiently or stablyexpressing P2X3 or P2X2/3 receptors. Cells are grown to confluence,washed, isolated, and stored as pellets at −80° C. until use. Somebinding studies require the addition Apyrase (Sigma-Aldrich) duringmembrane preparation to minimize receptor desensitization duringmembrane preparation. Membranes are prepared by resuspending the cellpellet in homogenization buffer, homogenizing, and centrifuging toobtain a membrane pellet. Total protein concentrations are determinedusing standard methods.

Displacement binding studies are conducted using procedures adapted fromJarvis et al. Under optimized conditions, ligand competition experimentsare conducted using radioligand ([3H]A-317491, Abbott), or other highaffinity compounds and a range of different concentrations of testcompounds in binding buffer. Ligand saturation studies are conductedusing a range of concentrations of radioligand. All binding reactionsare terminated by rapid filtration through a glass fiber filter.Membranes are washed, incubated in scintillant, and counted in ascintillation counter. IC50 values are determined using a four-parameterlogistic Hill equation.

Bladder Afferent Nerve Recordings:

In order to determine the precise role of inhibition of P2X3 and P2X2/3receptors in the micturition response, test compounds will be examinedfor their ability to modulate afferent signaling from the urinarybladder. Compounds will be evaluated in the urinary bladder/pelvic nervepreparation described by Vlaskovska et al., J. Neuroscience, 21:5670-7,2001, and Cockayne et al., J. Physiol. 567:621-39, 2005. Briefly, thewhole urinary tract attached to the lower vertebrae and surroundingtissues is isolated en bloc and superfused in a recording chamber withoxygenated (5% CO2 and 95% O2) Krebs solution. The bladder iscatheterized through the urethra for intraluminal infusion. A seconddouble lumen catheter is inserted into the bladder to measureintraluminal pressure and to drain the bladder. After the bladder isprepared, the pelvic nerve exiting the vertebrae is dissected andimpaled with a suction glass electrode. Nerve activity is measured usingstandard electrophysiological methods. Following a 60 min stabilizationperiod, repeated ramp distensions are performed until the afferentresponse stabilizes. This stabilized afferent response was used forcomparing mechanosensitivity of bladder afferents between differenttreatment groups.

Drug Metabolism and Pharmacokinetics

Caco-2 Permeability:

Caco-2 permeability is measured according to the method described inYee, Pharm. Res. 14:763-6, 1997. Caco-2 cells are grown on filtersupports (Falcon HTS multiwell insert system) for 14 days. Culturemedium is removed from both the apical and basolateral compartments andthe monolayers are preincubated with pre-warmed 0.3 ml apical buffer and1.0 ml basolateral buffer for 0.75 hour at 37° C. in a shaker water bathat 50 cycles/min. The apical buffer consists of Hanks Balanced SaltSolution, 25 mM D-glucose monohydrate, 20 mM MES Biological Buffer, 1.25mM CaCl₂ and 0.5 mM MgCl₂ (pH 6.5). The basolateral buffer consists ofHanks Balanced Salt Solution, 25 mM D-glucose monohydrate, 20 mM HEPESBiological Buffer, 1.25 mM CaCl₂ and 0.5 mM MgCl₂ (pH 7.4). At the endof the preincubation, the media is removed and test compound solution(10 μM) in buffer is added to the apical compartment. The inserts aremoved to wells containing fresh basolateral buffer and incubated for 1hr. Drug concentration in the buffer is measured by LC/MS analysis.

Flux rate (F, mass/time) is calculated from the slope of cumulativeappearance of substrate on the receiver side and apparent permeabilitycoefficient (Papp) is calculated from the following equation:Papp(cm/sec)=(F*VD)/(SA*MD)where SA is surface area for transport (0.3 cm²), VD is the donor volume(0.3 ml), MD is the total amount of drug on the donor side at t=0. Alldata represent the mean of 2 inserts. Monolayer integrity is determinedby Lucifer Yellow transport.Human Dofetilide Binding:

Cell paste of HEK-293 cells expressing the HERG product can be suspendedin 10-fold volume of 50 mM Tris buffer adjusted at pH 7.5 at 25° C. with2 M HCl containing 1 mM MgCl₂, 10 mM KCl. The cells are homogenizedusing a Polytron homogenizer (at the maximum power for 20 seconds) andcentrifuged at 48,000 g for 20 minutes at 4° C. The pellet isresuspended, homogenized and centrifuged once more in the same manner.The resultant supernatant is discarded and the final pellet wasresuspended (10-fold volume of 50 mM Tris buffer) and homogenized at themaximum power for 20 seconds. The membrane homogenate is aliquoted andstored at −80° C. until use. An aliquot is used for proteinconcentration determination using a Protein Assay Rapid Kit and ARVO SXplate reader (Wallac). All the manipulation, stock solution andequipment are kept on ice at all time. For saturation assays,experiments are conducted in a total volume of 200 μl. Saturation isdetermined by incubating 20 μl of [³H]-dofetilide and 160 μl of membranehomogenates (20-30 μg protein per well) for 60 min at room temperaturein the absence or presence of 10 μM dofetilide at final concentrations(20 μl) for total or nonspecific binding, respectively. All incubationsare terminated by rapid vacuum filtration over polyetherimide (PEI)soaked glass fiber filter papers using Skatron cell harvester followedby two washes with 50 mM Tris buffer (pH 7.5 at 25° C.). Receptor-boundradioactivity is quantified by liquid scintillation counting usingPackard LS counter.

For the competition assay, compounds are diluted in 96 wellpolypropylene plates as 4-point dilutions in semi-log format. Alldilutions are performed in DMSO first and then transferred into 50 mMTris buffer (pH 7.5 at 25° C.) containing 1 mM MgCl₂, 10 mM KCl so thatthe final DMSO concentration became equal to 1%. Compounds are dispensedin triplicate in assay plates (4 μl). Total binding and nonspecificbinding wells are set up in 6 wells as vehicle and 10 μM dofetilide atfinal concentration, respectively. The radioligand was prepared at 5.6×final concentration and this solution is added to each well (36 μl). Theassay is initiated by addition of YSi poly-L-lysine ScintillationProximity Assay (SPA) beads (50 μl, 1 mg/well) and membranes (110 μl, 20μg/well). Incubation is continued for 60 min at room temperature. Platesare incubated for a further 3 hours at room temperature for beads tosettle. Receptor-bound radioactivity is quantified by counting WALLACMICROBETA plate counter.

HERG Assay:

HEK 293 cells which stably express the HERG potassium channel are usedfor electrophysiological study. The methodology for stable transfectionof this channel in HEK cells can be found elsewhere (Zhou et al.,Biophys. J. 74:230-41, 1998). Before the day of experimentation, thecells are harvested from culture flasks and plated onto glass coverslipsin a standard Minimum Essential Medium (MEM) medium with 10% Fetal CalfSerum (FCS). The plated cells are stored in an incubator at 37° C.maintained in an atmosphere of 95% O₂/5% CO₂. Cells are studied between15-28 hrs after harvest.

HERG currents are studied using standard patch clamp techniques in thewhole-cell mode. During the experiment the cells are superfused with astandard external solution of the following composition (mM); NaCl, 130;KCl, 4; CaCl₂, 2; MgCl₂, 1; Glucose, 10; HEPES, 5; pH 7.4 with NaOH.Whole-cell recordings are made using a patch clamp amplifier and patchpipettes which have a resistance of 1-3 MOhm when filled with thestandard internal solution of the following composition (mM); KCl, 130;MgATP, 5; MgCl₂, 1.0; HEPES, 10; EGTA 5, pH 7.2 with KOH. Only thosecells with access resistances below 15 MΩ and seal resistances >1 GΩ areaccepted for further experimentation. Series resistance compensation wasapplied up to a maximum of 80%. No leak subtraction is done. However,acceptable access resistance depended on the size of the recordedcurrents and the level of series resistance compensation that can safelybe used. Following the achievement of whole cell configuration andsufficient time for cell dialysis with pipette solution (>5 min), astandard voltage protocol is applied to the cell to evoke membranecurrents. The voltage protocol is as follows. The membrane isdepolarized from a holding potential of −80 mV to +40 mV for 1000 ms.This was followed by a descending voltage ramp (rate 0.5 mV msec-1) backto the holding potential. The voltage protocol is applied to a cellcontinuously throughout the experiment every 4 seconds (0.25 Hz). Theamplitude of the peak current elicited around −40 mV during the ramp ismeasured. Once stable evoked current responses are obtained in theexternal solution, vehicle (0.5% DMSO in the standard external solution)is applied for 10-20 min by a peristalic pump. Provided there wereminimal changes in the amplitude of the evoked current response in thevehicle control condition, the test compound of either 0.3, 1, 3, 10 mMis applied for a 10 min period. The 10 min period included the timewhich supplying solution was passing through the tube from solutionreservoir to the recording chamber via the pump. Exposing time of cellsto the compound solution was more than 5 min after the drugconcentration in the chamber well reached the attempting concentration.There is a subsequent wash period of a 10-20 min to assessreversibility. Finally, the cells is exposed to high dose of dofetilide(5 mM), a specific IKr blocker, to evaluate the insensitive endogenouscurrent.

All experiments are performed at room temperature (23±1° C.). Evokedmembrane currents were recorded on-line on a computer, filtered at 500-1KHz (Bessel −3 dB) and sampled at 1-2 KHz using the patch clampamplifier and a specific data analyzing software. Peak currentamplitude, which occurred at around −40 mV, is measured off line on thecomputer.

The arithmetic mean of the ten values of amplitude is calculated undervehicle control conditions and in the presence of drug. Percent decreaseof IN in each experiment was obtained by the normalized current valueusing the following formula: IN=(1−ID/IC )×100, where ID is the meancurrent value in the presence of drug and IC is the mean current valueunder control conditions. Separate experiments are performed for eachdrug concentration or time-matched control, and arithmetic mean in eachexperiment is defined as the result of the study.

Half-Life in Human Liver Microsomes (HLM):

Test compounds (1 μM) are incubated with 3.3 mM MgCl₂ and 0.78 mg/mL HLM(HL101) in 100 mM potassium phosphate buffer (pH 7.4) at 37° C. on the96-deep well plate. The reaction mixture is split into two groups, anon-P450 and a P450 group. NADPH is only added to the reaction mixtureof the P450 group. An aliquot of samples of P450 group is collected at0, 10, 30, and 60 min time point, where 0 min time point indicated thetime when NADPH was added into the reaction mixture of P450 group. Analiquot of samples of non-P450 group is collected at −10 and 65 min timepoint. Collected aliquots are extracted with acetonitrile solutioncontaining an internal standard. The precipitated protein is spun downin centrifuge (2000 rpm, 15 min). The compound concentration insupernatant is measured by LC/MS/MS system. The half-life value isobtained by plotting the natural logarithm of the peak area ratio ofcompounds/internal standard versus time. The slope of the line of bestfit through the points yields the rate of metabolism (k). This isconverted to a half-life value using following equation:Half-life=ln 2/k.In Vivo Assays:

Various in vivo neuropathic, inflammatory, and visceral pain assays willbe conducted in male Sprague-Dawley rats weighing 250-350 g. Testcompounds may also be evaluated in models of bladder function. P2X3antagonists may be administered prior to or post-induction of the painmodel depending upon the specific model and the compound PKcharacteristics. The route of administration may includeintraperitoneal, (i.p.), subcutaneous (s.c.), oral (p.o.), intranvenous(i.v.), intrathecal (i.t.), or intraplantar. The endpoints for thesestudies may include mechanical allodynia, thermal hyperalgesia, coldallodynia, decreased formalin-induced pain responses, decreased writhingand contractions or altered bladder mechanosensation as appropriate forthe model as described below.

Neuropathic Pain Models

Chronic Constriction Injury Model (CCI or Bennett Model):

The CCI model is performed according to the method described by Bennettand Xie, Pain, 33:87-107, 1988. Briefly, under isoflurane anesthesia,the right sciatic nerve is exposed at mid-thigh level via bluntdissection through the biceps femoris. Proximal to the bifurcation ofthe sciatic nerve, about 7 mm of nerve is freed of adhering tissue and 4loose ligatures of 4.0 chromic gut are tied around the nerve. Spacingbetween ligatures is approximately 1 mm. The wound is closed in layers,and the skin closed with staples or non-silk sutures. Sham operatedanimals are treated identically with the exception that the sciaticnerve will not be ligated. Mechanical allodynia, cold allodynia, orthermal hyperalgesia testing occur 7-21 days post surgery.

Spinal Nerve Transection (SNT or Chung Model):

The SNT model will be performed according to the method described by Kimand Chung, Pain 50:355-363, 1992. Under isoflurane anesthesia, alongitudinal incision is made at the lower lumbar and sacral levels,exposing paraspinal muscles on the left side. The location of theincision is determined by the position of the L5 spinous process. Theparaspinal muscles are isolated and removed from the level of the L4spinous process to the sacrum. This opens up the space ventrolateral tothe articular processes, dorsal to the L6 transverse process, and medialto the ileum. Remaining connective tissues and muscles are removed.Under a dissecting microscope, the L6 transverse process, which coversthe L5 spinal nerve, is removed. Due to their close proximity, the L4and L5 spinal nerves may need to be separated to fully expose the L5spinal nerve for ligation using extra caution not to damage the L4 nerveduring this process. Animals that exhibit L4 nerve damage as evidencedby paw drop post-anesthesia are not included in studies. Once the L5spinal nerve is exposed, the nerve is ligated with 6-0 silk.Alternatively, the spinal nerve is cut distal to the ligation site. If amore complete neuropathy is required, then the L6 spinal nerve may alsobe ligated using the procedure described above. Sham operated animalsare treated identically with the exception that the nerves will not beligated/transected. Following spinal nerve ligation, hemostasis isconfirmed, the muscles are sutured in layers, and the skin is closedwith staples or non-silk sutures. Mechanical allodynia, cold allodynia,or thermal hyperalgesia testing occur 7-21 days post surgery.

Chemotherapy-Induced Painful Neuropathy:

Chemotherapy neuropathy is induced by i.p. administration of 1 mg/kgTaxol administered once/day on 4 alternating days (total dose=4 mg/kg)(Polomano et al., Pain, 94:293-304, 2001). Mechanical allodynia, coldallodynia, or thermal hyperalgesia testing occur 9-30 days post day 1 ofTaxol administration.

Inflammatory Pain Models

Formalin Model:

Test compounds are administered at various times prior to intraplantaradministration of formalin. A dilute solution of formalin (50 μL of 2.5%formaldehyde/saline) is administered s.c. into the plantar surface ofthe left hind paw under light restraint. Immediately followinginjection, animals are placed on a mesh stand inside a clear observationchamber large enough to allow for free movement of the animals duringthe study. Behaviors are scored using manual scoring or automatedscoring.

Manual scoring: Using a three channel timer, the observer records thetime (t in seconds) of decreased weight-bearing (t₁), paw lifting (t₂),and licking/biting/shaking (t₃). Results are weighted according to themethod of Dubuisson and Dennis, Pain, 4:161-174, 1977, using the formulat₁+2t₂+3t₃/180 where 180 s is the evaluation time for each increment.Behaviors are acquired in alternating 3 min increments starting attime=0 min (i.e. 0-3 min, 6-9 min etc.) and ending at 60 min.

Automated scoring: A small metal band weighing 0.5 g is placed on theleft paw. Formalin is administered and the animal placed unrestrainedinside an observation chamber over an electromagnetic detector system(Automated Nociception Analyzer, University of California, San Diego).The number of paw flinches are electronically recorded.

Complete Freund's Adjuvant Model (CFA):

Animals receive a s.c. injection of 100 μL complete Freund's adjuvantcontaining 100 μg Mycobacterium tuberculosis strain H37Ra into theplantar surface of the right hind paw under isoflurane anesthesia.Swelling and inflammation are visible within 1 h after administration.Mechanical allodynia or thermal hyperalgesia testing start 24 h post CFAadministration.

Carageenan:

Animals receive a subcutaneous injection of 100 μL of either 2%carrageenan or saline (controls) into the plantar surface of the righthind paw under isoflurane anesthesia. Swelling and inflammation arevisible within 1 h after administration. Mechanical allodynia or thermalhyperalgesia testing start 3-24 h post carageenan administration(Hargreaves et al., Pain, 32:77-88, 1988).

ATP and α,β-methylene (αβmeATP) ATP-Induced Inflammatory Pain:

Rats are administered up to 100 nmol αβmeATP, ATP, adenosine, or PBS ina volume up to 100 μL subcutaneously in the plantar surface of the lefthindpaw under light restraint. Immediately following injection, animalsare placed on a mesh stand inside a clear observation chamber largeenough to allow for free movement of the animals. The duration offlinching and licking are recorded over a 4 min interval to evaluatenocifensive behavior. Following nocifensive screening, behavioraltesting including measures of mechanical allodynia and thermalhyperalgesia are acquired for up to 6 h post administration.

Visceral Pain Models

Colo-Rectal Distension (CRD):

Prior to induction of the model, animals are deprived of food butallowed access to water ad libitum for 16 h prior to the induction ofthe model. A 5 cm latex balloon is attached to a barostat systemcomposed of a flow meter and pressure control program by a length oftubing. Under isoflurane anesthesia, the balloon is inserted into thedistal colon via the anus at a distance of 5 cm from the anus and tapedto the base of the tail. Post-anesthesia, the animal is placedunrestrained into a clean polypropylene cage and allowed to acclimatefor 30 mins. The balloon is progressively inflated from 0-75 mmHg in 5mm increments every 30 s. The colonic reaction threshold is defined asthe pressure inducing the first abdominal contraction. Abdominalcontraction indicative of visceral pain correlates with hunching,hump-backed position, licking of the lower abdomen, repeated waves ofcontraction of the ipsilateral oblique musculature with inward turningof the ipsilateral hindlimb, stretching, squashing of the lower abdomenagainst the floor (Wesselman, Neurosci. Lett., 246:73-76, 1998).

Acetic Acid Writhing Test:

A 0.6% solution of acetic acid (10 ml/kg) is administered i.p. to ratsand the number of abdominal constrictions over 30 min are counted.

Behavioral Testing

Mechanical Testing:

Mechanical allodynia testing is performed using the up-down method ofDixon, Ann. Rev. Pharmacol. Toxicol. 20:441-462, 1980, modified formechanical thresholds by Chaplan et al., J. Neurosci. Methods 53:55-63,1994. Testing is performed during the day portion of the circadian cycle(7:00-19:00). Animals are placed in separate plastic enclosures with amesh bottom which allowed for full access to the paws. For all tests,animals are acclimated to the apparatus for at least 15 min prior totesting or until cage exploration and major grooming activities haveceased. The area tested will be the mid-plantar hind paw. The paw istouched with 1 of a series of 8 von Frey hairs (Stoelting, Wood Dale,Ill.) with logarithmically incremental stiffness (0.4, 0.6, 1.4, 2, 4,6, 8, and 15 g). Each von Frey hair is presented perpendicularly to theplantar surface with sufficient force to cause slight buckling againstthe paw and held for approximately 6-8 s. Stimulation is presented atintervals of several seconds, allowing for apparent resolution of anybehavioral responses to previous stimuli. A positive response will benoted if the paw was sharply withdrawn. Flinching immediately uponremoval of the hair will also be considered a positive response.Ambulation will be considered an ambiguous response and in such cases,the stimulus will be repeated.

To determine the 50% withdrawal threshold, testing will be initiatedwith the 2 g fiber (the middle fiber in the series). Fibers will bepresented in a consecutive fashion whether ascending or descending. Inthe absence of a paw withdrawal response to the initially selectedfiber, the next highest fiber was presented. In the event of a pawwithdrawal, the next weaker fiber was presented. The optimal thresholdcalculation by this method requires 6 responses in the immediatevicinity of the 50% withdrawal threshold. Counting of the critical 6data points will not begin until the response threshold is first crossedat which time the 2 responses straddling the threshold will bedesignated as the first 2 responses of the series of 6. Four additionalresponses to the continued presentation of the fibers constituted theremaining 4 responses.

In cases where continuous positive or negative responses are observed tothe exhaustion of the fiber set, values of 15 g and 0.25 g wereassigned, respectively.

The range of fibers tested in this paradigm have not been shown to causetissue damage although prolonged stimulation over short time intervalsmay result in sensitization and/or habituation, scenarios which wouldlead to decreased or increased thresholds, respectively. Therefore,there is a minimum 1 h interval between testing sessions with no morethan 4 testing sessions per day. For testing intervals, animals arereturned to their cages following all testing sessions. Testing sessionswill last no longer than 1 h. No two testing sessions will occur onconsecutive hours. To minimize distress, mechanical allodynia testing isconducted no more than 4 times per day.

Thermal Testing:

To measure heat thermal hyperalgesia, an Ugo Basile radiant heat source(I.R. intensity of 40) will be provided by a light bulb focused onto theplantar surface of the paw (Hargreaves et al., Pain 32:77-88, 1988). Pawwithdrawal latencies are defined as the time it takes for the animal toremove its paw from the heat source. To ensure that no tissue damageoccurs, all tests will have a 20 sec cutoff even when the animal doesnot withdraw its paw away from the heat stimulation. The test consistsof 3 measurements of the same paw, with a minimum 5 minute intervalsbetween each determination. To minimize distress, thermal testing isconducted no more than 3 times per day.

Cold Testing:

To measure cold allodynia, a drop of acetone is applied to the plantarsurface of the paw through the underside of the grating on which theanimals are standing using a 50 μL Hamilton syringe. The process isperformed 5 times with a 3 min interval between each time. Vigorousshaking will be recorded as a positive response. The acetone drop testis conducted no more than 5 times over the course of a study (includingthe pre-surgery baseline test) and no more than once per day (Kotinen etal., Pain 80:341-346, 1999).

Assays of Urinary Function

Bladder Cystometry:

Animals are anaesthetized, and transurethral closed cystometry wasconducted as previously described (Dmitrieva et al., Neuroscience78:449-59, 1997; Cockayne et al., Nature 407:1011-5, 2000). The bladderis catheterized cannulated transurethrally with a PE-10 polypropylenecatheter. Each cystometrogram consists of slowly filling the bladderwith normal saline via the transurethral catheter, and then recordingthe pressure associated with filling via a pressure transducer.Contractions greater than a predetermined threshold value areinterpreted as micturition contractions. For each cystometrogram, thevolume at which active contractions occurred (micturition threshold) andthe number of contractions per cystometrogram are recorded.

Neuropathic Pain Measurements using Chung Model

Under pentobarbital anesthesia (60 mg/kg, i.p.), rats are placed in aprone position on a flat, sterile surface. A midline incision from L4-S2is made and the left paraspinal muscles are separated from the spinousprocesses. The L5 and L6 spinal nerves are tightly ligated with a 4-0silicon-treated silk suture, according to the method described by Kimand Chung, Pain, 50:355-363, 1992. The L4 spinal nerve is carefullypreserved from being surgically injured. The skin is closed with woundclips and animals are returned to their home cages. Rats exhibitingprolonged postoperative neurological deficits or poor grooming areexcluded from the experiments. The animals are assessed for response tonoxious mechanical stimuli by determining paw withdrawal threshold(PWT), as described below, prior to surgery (baseline), then immediatelyprior to and at various timepoints after being administered with a fusedheterocyclic compound of this invention (30 mg/kg) in the left rear pawof the animal. Additionally, other animals may also be assessed forthermal or mechanical hyperalgesia, as described below.

Assessment of Tactile Allodynia: To assess tactile allodynia, rats areplaced in clear, plexiglass compartments with a wire mesh floor andallowed to habituate for a period of at least 15 minutes. Afterhabituation, a series of von Frey monofilaments are presented to theplantar surface of the left (operated) foot of each rat. The series ofvon Frey monofilaments consists of six monofilaments of increasingdiameter, with the smallest diameter fiber presented first. Five trialsare conducted with each filament with each trial separated byapproximately 2 minutes. Each presentation lasts for a period of 4-8seconds or until a nociceptive withdrawal behavior is observed.Flinching, paw withdrawal or licking of the paw are considerednociceptive behavioral responses.

Response to Thermal Stimuli as an Assessment of Thermal Hyperalgesia:The plantar test can be used to assess thermal hyperalgesia. For thistest, hind paw withdrawal latencies to a noxious thermal stimulus aredetermined using a plantar test apparatus (commercially available fromUgo Basile of Italy) following the technique described by Hargreaves etal., Pain 32: 77-88, 1988. The maximum exposure time is set at 32seconds to avoid tissue damage and any directed paw withdrawal from theheat source is taken as the end point. Three latencies are determined ateach time point and averaged. Only the affected (ipsilateral) paw istested. An increase latency of paw withdrawal demonstrates reversal ofhyperalgesia.

Response to Mechanical Stimuli as an Assessment of MechanicalHyperalgesia: The paw pressure assay can be used to assess mechanicalhyperalgesia. For this assay, hind paw withdrawal thresholds (PWT) to anoxious mechanical stimulus are determined using an analgesymeter (Model7200, commercially available from Ugo Basile of Italy) as described inStein et al., Pharmacol. Biochem. Behav. 31:451-455, 1988. The maximumweight that can be applied to the hind paw is set at 250 g and the endpoint is taken as complete withdrawal of the paw. PWT is determined oncefor each rat at each time point and only the affected (ipsilateral) pawis tested.

ACTIVITY OF COMPOUNDS OF THE INVENTION

A calcium uptake assay was performed as described in paragraphs [00341]to [00340] above. The % Inhibition data for the representative compoundsare given in Table 4 below. In Table 4, activity of each compound isexpressed as follows: TABLE 4 MW MW Ca Influx P2X2/3C % ID (calcd)(obsd) Inhibition at 3 μM/10 μM 1 403.82 403.40 2 337.81 339.20 +/ 3355.80 356.00 4 406.80 407.80  /* 5 450.44 450.90 6 469.87 470.20 +/ 7513.52 515.30 8 374.44 374.70 9 370.38 370.60 10 384.40 385.70  /* 11384.40 384.60 12 384.40 385.90  /* 13 420.90 421.40  /* 14 448.96 449.2015 406.92 407.40  /* 16 420.95 421.50 +/ 17 394.91 394.80  /* 18 381.52382.3  /* 19 385.39 385.40 20 433.86 433.60 21 323.44 324.30 22 391.44391.80 23 365.87 366.10 24 345.45 345.80    /**** 25 365.87 366.20++++/   26 337.47 338.40    /**** 27 361.45 362.36    /**** 28 361.45362.35  ++++/**** 29 427.59 428.00 30 365.87 366.19 ++++/   31 375.47375.70 32 379.89 380.30  ++++/**** 33 389.54 390.40 34 405.81 406.00 35375.47 376.36 ++++/   36 345.45 346.24 +/ 37 375.43 376.26 ++++/   38399.42 400.17 +++/  39 399.42 400.18 +++/  40 415.42 416.31 +++/  41415.42 416.31 42 415.42 416.31 ++++/   43 357.46 358.26 44 387.53 388.40+/ 45 345.45 346.22 ++++/   46 375.47 376.36 ++++/   47 405.50 406.36+++/  48 379.89 380.30 ++++/   49 359.47 360.29 ++++/   50 399.42 400.17++++/   51 405.50 406.35 +++/  52 397.43 398.22 ++++/   53 361.45 362.33++++/   54 414.34 414.17 +++/  55 365.87 366.20 ++++/   56 345.45 346.20++++/   57 349.41 350.32 ++++/   58 373.50 374.22 +/ 59 405.50 406.35  ++/**** 60 391.49 61 413.44 414.22  ++++/**** 62 379.89 380.30 +/ 63375.47 376.35 +/ 64 375.47 376.34 +/ 65 373.50 374.22 +/ 66 379.89380.30 +/ 67 363.44 364.32   +/*** 68 375.47 376.35 +/ 69 413.44 414.22+/ 70 359.47 360.29 ++/  71 367.40 368.1 +++/  72 367.40 73 367.40367.00 ++++/   74 417.41 417.90 +/ 75 417.41 418.4 +/ 76 417.41 417.00+/ 77 367.40 368.0 ++++/   78 400.31 400.00 +/ 79 359.47 360.4 ++/  80359.47 360.4 +/ 81 359.47 82 397.43 83 383.86 384.0 +++/  84 391.47391.00 85 400.31 399.00 +/ 86 363.44 363.00 ++++/   87 391.47 392.2 +/88 391.47 391.00 89 433.86 435.00  +/* 90 332.41 333.9 91 332.41 332.0092 345.45 345.00 93 349.41 349.00 94 359.47 359.00 95 359.47 359.00 96359.47 359.00 97 359.47 359.00 98 363.44 363.00 ++++/   99 363.44 364.00100 367.40 367.00 101 367.40 367.00 102 379.89 380.00 103 379.89 379.00104 379.89 379.00 105 379.89 379.00 106 381.43 381.00 107 382.47 382.00108 383.86 384.00 109 383.86 384.00 110 383.86 384.00 111 383.86 383.00+++/  112 383.86 384.00 113 391.47 391.00 114 391.47 391.00 115 400.31400.00 +/ 116 400.31 400.00 117 413.44 414.00 118 417.41 417.00 119417.41 417.00 120 417.41 417.00 121 417.41 417.00 ++++/   122 417.41417.00 123 423.54 424.00 124 423.52 423.00 125 467.42 466.00 +/ 126363.44 363.00 127 433.86 433.80 128 379.89 381.8 129 379.89 381.1+ compound exhibited 0-25% inhibition at 3 μM++ compound exhibited 25-50% inhibition at 3 μM+++ compound exhibited 50-75% inhibition at 3 μM++++ compound exhibited 75% or greater inhibition at 3 μM* compound exhibited 0-25% inhibition at 10 μM** compound exhibited 25-50% inhibition at 10 μM*** compound exhibited 25-50% inhibition at 10 μM**** compound exhibited 25-50% inhibition at 10 μM.

At least some of the chemical names of compounds of the invention asgiven and set forth in this application, may have been generated on anautomated basis by use of a commercially available chemical namingsoftware program, and have not been independently verified.Representative programs performing this function include the Lexichemnaming tool sold by Open Eye Software, Inc. and the Autonom Softwaretool sold by MDL, Inc.

from the foregoing description, various modifications and changes in thecompositions and methods of this invention will occur to those skilledin the art. All such modifications coming within the scope of theappended claims are intended to be included therein.

All publications, including but not limited to patents and patentapplications, cited in this specification are herein incorporated byreference as if each individual publication were specifically andindividually indicated to be incorporated by reference herein as thoughfully set forth.

1. A compound having a formula 1:

wherein A and B are independently selected from CR^(2′)R^(2′), CO, andCS; Y is CR^(2′)R^(2′); W is selected from CR⁴ and N; Z is selected fromO and NR²; L is C₁-C₉ alkylene or C₁-C₉ heteroalkylene; R¹ is acarbocyclic group or a heterocyclic group; R² is selected from hydrogen,C₁-C₆ alkyl, C₃-C₈ cycloalkyl; each R^(2′) is selected from hydrogen,C₁-C₆ alkyl, C₃-C₈ cycloalkyl, aryl and aralkyl; R³ is a carbocyclicgroup or a heterocyclic group; R⁴ is selected from H, alkyl, acyl,acylamino, alkylamino, alkythio, alkoxy, alkoxycarbonyl, alkoxycarbonyl,alkylarylamino, arylalkyloxy, arylalkyloxy, amino, aryl, aryl,arylalkyl, sulfoxide, sulfone, sulfanyl, aminosulfonyl, arylsulfonyl,sulfuric acid, sulfuric acid ester, dihydroxyphosphoryl,aminodihydroxyphosphoryl, azido, carbamoyl, carboxyl, cyano, cycloalkyl,cycloheteroalkyl, dialkylamino, halo, heteroaryloxy, heteroaryl,heteroalkyl, hydroxy, nitro, and thio; and R^(4′) is selected from R⁴and -Z′-L′-R⁴, wherein Z′ is a bond, NR^(2′), O, S, SO, SO₂, COO, orCONR^(2′) and L′ is (C₁-C₆)alkylene; or a pharmaceutically acceptablesalt, solvate, prodrug, stereoisomer, tautomer or isotopic variantthereof
 2. A compound having a formula 1:

wherein A and B are independently selected from CR^(2′)R^(2′), CO, andCS; Y is CR^(2′)R^(2′); W is selected from CR⁴ and N; Z is selected fromO and NR²; L is a bond; R¹ is a carbocyclic group or a heterocyclicgroup; R² is selected from hydrogen, C₁-C₆ alkyl, C₃-C₈ cycloalkyl; eachR^(2′) is selected from hydrogen, C₁-C₆ alkyl, C₃-C₈ cycloalkyl, aryland aralkyl; R³ is a carbocyclic group or a heterocyclic group; R⁴ isselected from H, alkyl, acyl, acylamino, alkylamino, alkythio, alkoxy,alkoxycarbonyl, alkoxycarbonyl, alkylarylamino, arylalkyloxy,arylalkyloxy, amino, aryl, aryl, arylalkyl, sulfoxide, sulfone,sulfanyl, aminosulfonyl, arylsulfonyl, sulfuric acid, sulfuric acidester, dihydroxyphosphoryl, aminodihydroxyphosphoryl, azido, carbamoyl,carboxyl, cyano, cycloalkyl, cycloheteroalkyl, dialkylamino, halo,heteroaryloxy, heteroaryl, heteroalkyl, hydroxy, nitro, and thio; andR^(4′) is selected from R⁴ and -Z′-L′-R⁴, wherein Z′ is a bond, NR^(2′),O, S, SO, SO₂, COO, or CONR^(2′) and L′ is (C₁-C₆)alkylene; or apharmaceutically acceptable salt, solvate, prodrug, stereoisomer,tautomer or isotopic variant thereof, with the proviso that the compoundis not3-chloro-7-cyclohexyl-1-(cyclohexylamino)-5,6,7,8-tetrahydro-2,7-naphthyridine-4-carbonitrile;7-cyclohexyl-1-(cyclohexylamino)-5,6,7,8-tetrahydro-3-(1-piperidinyl)-2,7-naphthyridine-4-carbonitrile;or7-cyclohexyl-1-(cyclohexylamino)-5,6,7,8-tetrahydro-3-(4-morpholinyl)-2,7-naphthyridine-4-carbonitrile.3. A compound according claim 1, wherein L is branched C₁-C₉ alkylene,substituted C₁-C₉ alkylene, branched C₁-C₉ heteroalkylene or substitutedC₁-C₉ heteroalkylene.
 4. A compound according to claim 1, wherein L isunsubstituted C₁-C₉ alkylene or unsubstituted C₁-C₉ heteroalkylene.
 5. Acompound according to claim 1, wherein Z is O.
 6. A compound accordingto claim 1, wherein Z is NR².
 7. A compound according to claim 1,wherein Z is NH.
 8. A compound according to claim 7, wherein R⁴ is H. 9.A compound according to claim 1, having a formula 2:

wherein W, Z, L, R¹, R³ and R^(4′) are as defined in claim
 1. 10. Acompound according to claim 9, wherein W is selected from CR⁴ and N; Zis NH; R³ is selected from aryl, heteroaryl, cycloalkyl,cycloheteroalkyl, cycloalkenyl, cycloheteroalkenyl, bicycloalkyl,bicycloheteroalkyl, bicycloalkenyl, bicycloheteroalkenyl, bicycloaryl,and bicycloheteroaryl ring; and R^(4′) is H.
 11. A compound according toclaim 10, wherein L is selected from —CH₂—, —CHMe—, —CMe₂—, —(CH₂)₂—,—CMe₂—CH₂—, —(CH₂)₃—, —(CH₂)₄—, —CH(CH₃)CH₂—, —(CH₂)₂SCH₂—,—(CH₂)₂—SO₂CH₂—, —CH(CH₂CH₃)CH₂OCH₂—, —CH₂CHF—, —CH₂CF₂—, —CH₂CH(OH)—and —CH₂CO—.
 12. A compound according to claim 11, wherein L is selectedfrom —CH₂—, —CHMe—, —CMe₂—, —(CH₂)₂—, —CMe₂—CH₂— and —(CH₂)₃—.
 13. Acompound according to claim 10, wherein R¹ is aryl, heteroaryl,bicycloaryl, bicycloalkyl, or bicycloheteroaryl.
 14. A compoundaccording to claim 10, wherein R¹ is substituted or unsubstitutedcycloalkyl.
 15. A compound according to claim 10, wherein wherein R¹ isselected from substituted or unsubstituted quinoline, isoquinoline,methylenedioxyphenyl, and indole.
 16. A compound according to claim 10,wherein R¹ is

and wherein subscript n′ is selected from 1-5 and each R⁵ isindependently selected from hydrogen, substituted or unsubstitutedalkyl, substituted or unsubstituted acyl, substituted or unsubstitutedacylamino, substituted or unsubstituted alkylamino, substituted orunsubstituted alkythio, substituted or unsubstituted alkoxy, aryloxy,alkoxycarbonyl, substituted alkoxycarbonyl, substituted or unsubstitutedalkylarylamino, arylalkyloxy, substituted arylalkyloxy, amino, aryl,substituted aryl, arylalkyl, substituted or unsubstituted sulfoxide,substituted or unsubstituted sulfone, substituted or unsubstitutedsulfanyl, substituted or unsubstituted aminosulfonyl, substituted orunsubstituted arylsulfonyl, sulfuric acid, sulfuric acid ester,substituted or unsubstituted dihydroxyphosphoryl, substituted orunsubstituted aminodihydroxyphosphoryl, azido, substituted orunsubstituted carbamoyl, carboxyl, cyano, substituted or unsubstitutedcycloalkyl, substituted or unsubstituted cycloheteroalkyl, substitutedor unsubstituted dialkylamino, halo, heteroaryloxy, substituted orunsubstituted heteroaryl, substituted or unsubstituted heteroalkyl,hydroxy, nitro, and thio.
 17. A compound according to claim 16, whereinsubscript n′ is 1, 2 or
 3. 18. A compound according to claim 16, whereinsubscript n′ is 1 or
 2. 19. A compound according to claim 16, whereineach R⁵ is independently selected from Me, Et, Pr, iso-Pr, Ph, Cl, F,Br, CN, OH, OMe, OEt, OPh, COPh, CO₂Me, CH₂-N-morpholino,CH₂—N—(4-Me-piperidino), CONH₂, CF₃, CHF₂, OCF₃, OCHF₂, t-Bu, SMe,CH═CH—CO₂H, SOMe, SO₂Me, SO₂CF₃, SO₂NH₂, SO₃H, SO₃Me, and pyridyl.
 20. Acompound according to claim 10, wherein R³ is

and wherein subscript n′ is selected from 1-5 and each of R⁵ isindependently selected from hydrogen, substituted or unsubstitutedalkyl, substituted or unsubstituted acyl, substituted or unsubstitutedacylamino, substituted or unsubstituted alkylamino, substituted orunsubstituted alkythio, substituted or unsubstituted alkoxy, aryloxy,alkoxycarbonyl, substituted alkoxycarbonyl, substituted or unsubstitutedalkylarylamino, arylalkyloxy, substituted arylalkyloxy, amino, aryl,substituted aryl, arylalkyl, substituted or unsubstituted sulfoxide,substituted or unsubstituted sulfone, substituted or unsubstitutedsulfanyl, substituted or unsubstituted aminosulfonyl, substituted orunsubstituted arylsulfonyl, sulfuric acid, sulfuric acid ester,substituted or unsubstituted dihydroxyphosphoryl, substituted orunsubstituted aminodihydroxyphosphoryl, azido, substituted orunsubstituted carbamoyl, carboxyl, cyano, substituted or unsubstitutedcycloalkyl, substituted or unsubstituted cycloheteroalkyl, substitutedor unsubstituted dialkylamino, halo, heteroaryloxy, substituted orunsubstituted heteroaryl, substituted or unsubstituted heteroalkyl,hydroxy, nitro, and thio.
 21. A compound according to claim 20, whereinR³ is


22. A compound according to claim 20 or 21, wherein subscript n′ is 1, 2or
 3. 23. A compound according to claim 20 or 21, wherein subscript n′is 1 or
 2. 24. A compound according to claim 20 or 21, wherein each R⁵is independently selected from Me, Et, Pr, iso-Pr, Ph, Cl, F, CN, OH,OMe, OEt, OPh, CF₃, CHF₂, OCF₃, OCHF₂, t-Bu, SO₂Me, SO₂CF₃, and SO₃Me.25. A compound according to claim 10, wherein R³ is


26. A compound according to claim 25, wherein R³ is


27. A compound according to claim 1, wherein W is CH.
 28. A compoundaccording to claim 1, wherein W is N.
 29. A compound according to claim1, selected from the group consisting of:(2,3-Difluoro-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;(4-Fluoro-3-methyl-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;and(2-Fluoro-4-trifluoromethyl-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;or a pharmaceutically acceptable salt, solvate, prodrug, stereoisomer,tautomer or isotopic variant thereof.
 30. A compound according to claim1, selected from the group consisting of:(2-Methyl-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;(4-Chloro-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;Cyclohexylmethyl-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;(2-Methoxy-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;(3-Methoxy-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;(2-Chloro-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;[2-(2-Chloro-phenyl)-ethyl]-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;[2-(4-Methoxy-phenyl)-ethyl]-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;Benzo[1,3]dioxol-5-ylmethyl-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;[6-(5-Methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-(2-trifluoromethoxy-benzyl)-amine;[6-(5-Methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-phenethyl-amine;[2-(3-Methoxy-phenyl)-ethyl]-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;[2-(4-Chloro-phenyl)-ethyl]-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;[6-(5-Methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-(2-p-tolyl-ethyl)-amine;[6-(5-Methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-(4-trifluoromethyl-benzyl)-amine;(2-Difluoromethoxy-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;(4-Methoxy-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;(3-Chloro-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;(4-Methyl-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;(3-Fluoro-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;[6-(5-Methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-[2-(3-trifluoromethyl-phenyl)-ethyl]-amine;(3,4-Difluoro-benzyl)-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;and[1-(4-Fluoro-phenyl)-ethyl]-[6-(5-methyl-pyridin-2-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-yl]-amine;or a pharmaceutically acceptable salt, solvate, prodrug, stereoisomer,tautomer or isotopic variant thereof.
 31. A pharmaceutical compositioncomprising a pharmaceutically acceptable carrier and a pharmaceuticallyeffective amount of a compound of claim
 1. 32. The pharmaceuticalcomposition of claim 31, wherein the carrier is a parenteral carrier.33. The pharmaceutical composition of claim 31, wherein the carrier isan oral carrier.
 34. The pharmaceutical composition of claim 31, whereinthe carrier is a topical carrier.
 35. The pharmaceutical composition ofclaim 31, wherein the carrier is a parenteral carrier.
 36. A method forpreventing, treating or ameliorating in a mammal a disease or conditionwhich comprises administering to the mammal an effectivedisease-treating or condition-treating amount of a pharmaceuticalcomposition according to claim
 31. 37. The method of claim 36, whereinthe disease or condition is selected from: pain including acute,inflammatory and neuropathic pain, chronic pain, dental pain andheadache including migraine, cluster headache and tension headache,Parkinson's disease, Alzheimer's disease and multiple sclerosis;diseases and disorders which are mediated by or result inneuroinflammation, encephalitis; centrally-mediated neuropsychiatricdiseases and disorders, depression mania, bipolar disease, anxiety,schizophrenia, eating disorders, sleep disorders and cognitiondisorders; neurological and neurodegenerative diseases and disorders;epilepsy and seizure disorders; prostate, bladder and bowel dysfunction,urinary incontinence, urinary hesitancy, rectal hypersensitivity, fecalincontinence, benign prostatic hypertrophy and inflammatory boweldisease; respiratory and airway disease and disorders, allergicrhinitis, asthma and reactive airway disease and chronic obstructivepulmonary disease; diseases and disorders which are mediated by orresult in inflammation, arthritis, rheumatoid arthritis andosteoarthritis, myocardial infarction, autoimmune diseases anddisorders, itch / pruritus, psoriasis; obesity; lipid disorders; cancer;and renal disorders.
 38. The method of claim 37, wherein the disease orcondition is Parkinson's disease.
 39. The method of claim 37, whereinthe disease or condition is Alzheimer's disease.
 40. The method of claim37, wherein the disease or condition is pain.
 41. The method of claim40, wherein the pain is associated with a condition selected from thegroup consisting of postmastectomy pain syndrome, stump pain, phantomlimb pain, oral neuropathic pain, Charcot's pain, toothache, venomoussnake bite, spider bite, insect sting, postherpetic neuralgia, diabeticneuropathy, reflex sympathetic dystrophy, trigeminal neuralgia,osteoarthritis, rheumatoid arthritis, fibromyalgis, Guillain-Barresyndrome, meralgia paresthetica, burning-mouth syndrome, bilateralperipheral neuropathy, causalgia, sciatic neuritis, peripheral neuritis,polyneuritis, segmental neuritis, Gombault's neuritis, neuronitis,cervicobrachial neuralgia, cranial neuralgia, egniculate neuralgia,glossopharyngial neuralgia, migranous neuralgia, idiopathic neuralgia,intercostals neuralgia, mammary neuralgia, mandibular joint neuralgia,Morton's neuralgia, nasociliary neuralgia, occipital neuralgia, redneuralgia, Sluder's neuralgia splenopalatine neuralgia, supraorbitalneuralgia, vidian neuralgia, sinus headache, tension headache, labor,childbirth, intestinal gas, menstruation, cancer, and trauma.
 42. Themethod of claim 37, wherein the disease or condition is neuropathicpain.
 43. The method of claim 37, wherein the disease or condition is anautoimmune disease.
 44. The method of claim 37, wherein the disease orcondition is an inflammatory disease or condition.
 45. The method ofclaim 37, wherein the disease or condition is a neurological orneurodegenerative disease or condition.
 46. A method of treating amammal suffering from at least one symptom selected from the groupconsisting of symptoms of exposure to capsaicin, symptoms of burns orirritation due to exposure to heat, symptoms of burns or irritation dueto exposure to light, symptoms of burns, bronchoconstriction orirritation due to exposure to tear gas, and symptoms of burns orirritation due to exposure to acid, which comprises administering to themammal an effective disease-treating or condition-treating amount of apharmaceutical composition of claim 31.